People here are already complaining about how an LFG-Addon would ruin classic; that's absolutely ridiculous.
My opinion is: Not even an automatic LFG-Addon (that has teleport disabled) would ruin classic at all. People here are so overestimating the grouping up in classic. Sorry, but in reality in 90% of the time the only thing i said before the raid was: invite. That's all of the so called social interaction before the group was full.
Many groups didn't talked at all there. and even LFG could not ruin this at all with the premise that there was no teleport. I think that there are many reasons why WoW-Classic was so much better in social interactions.
First: DUNGEONS ARE NOT ONLY THE INSTANCE. Dungeons were better in Vanilla than sadly in every expansion later. There was a dungeon BEFORE the dungeon, with elites, so you couldn't simply go in there. Except for the endgame-dungeons, most leveling-dungeons required you do go in there and defeat some elite before the dungeon-entrace. They were by far not so easy and
Look at Maraudon: the best part of the dungeon was actually OUTSIDE of the dungeon. How beautiful the entrance was, how much you lost when you only teleported in. Dungeons should have already a difficulty before you join the instance. This feeling that your group is not the only one that challenge the dungeon, the quests that leads from outside into the dungeon, the feeling that you are already inside of it with many other groups AND that you not only join in as a group, but as a big world inside the dungeon makes classic in this regard SO MUCH BETTER.
The teleport actually ruins dungeons with the LFG-Addon, but not an automatic-search for group members itself.
Second: the next reason is: DUNGEONS ARE NOT HALLWAYS. Dungeons are more than: Trash - Boss - Trash - Boss - Trash - Endboss in a gigantic hallways. Look at BRD. You go into a CITY, Not a gigantic hallway. There were Secrets, there were closed doors, there were Quests that you need to do before you can actually do the dungeon at all. In Vanilla, Dungeons were dungeons, a mysterious place that you need to discover. There were many secrets, many hidden bosses, interactions, another corridor with either NOTHING or a HIDDEN BOSS, a special event, or whatever.
THAT IS THE CORE OF A DUNGEON.
Sadly because the most popular dungeon was Scarlet Monastery (but that's because leveling from 30 to 40 even in vanilla was the most easy there) blizzard decided to create dungeons like in scarlet monastery after all. Only a hallway, nothing more.
And Third: DUNGEONS ARE NO E-SPORT. E-Sport crap did not exist back then as it is now. Nowadays dungeons are sadly designed with speed and e-sport in mind to please their shareholders, because there's money on the table with e-sport. It doesn't matter that they ruins it for their core-audience: e-sport, money table: GIEF, that's the view of the shareholders.
It doesn't matter that dungeons became boring because of this. Ever since BC we only had hallway-dungeons, but there and WotLK, they were at least not as boring as they are now. Even back then they were quite some exceptions: Halls of Reflection, Halls of Stone (back then, it was not as easy and a cakewalk as it is now), Arkatraz with a significant higher difficulty, and so on.
Right now, Dungeons are simply all boring. Back then they were so much slower, you needed CC, you needed anything in your toolkit to challenge them, and they were so much more satisfactory. But now, the only premise is gogogo, fast faster fastest and pull anything that you can, it's all about speed. Back then, the trash were really challenging, but also satisfactory; and meaningful, since much of the dungeon-loot could also drop from them.
Sometimes, there were only a few trash that were difficult to kill, but when you killed them, you had a long way without any enemies at all. Sometimes there was an abundance of trash that you need to kill fast before they respawned.
Here we come to the Fourth reason: RESPAWN was also a meaningful factor in dungeons: Sometimes, when you wiped, you either need to do the whole dungeon-trash again or you better even resetted the instance. Yes, was it sometimes a real pain in the ass? For Sure, but RESPAWN allowed people to get better in the dungeon, since they knew: if they screw up now, they would not have a good time anymore.
Oh and last but NOT least: LFG was not only necessary in Dungeons. In Vanilla. we had dungeons that WERE NO DUNGEONS. ELITE QUEST ZONES like in the Hinterlands, where you had a big troll-city to go into. ELITE QUEST ZONES were far more attractive to social interactions than ANYTHING ELSE. That's something that is really missing nowadays. Quests where you needed to go into a group. That's nothing bad on them, the issue is nowadays not that there are dailys were you need to join a group, but that there
Also a reason why flying was probably a big mistake: They can't do elite-zones anymore with challenge in mind. You needed to go up to the troll-city to kill this enemy. then ride through it. You can't because they are killing you: group up with others who need to do it too. That leads to more social interaction, that leads to friendships.
Oh and something else too: When blizzard created Cross Realm Zones. Yes, CRZ are hated too, but not because they are cross realm. The BIG ISSUE IS that when blizzard created them, they totally destroyed the social interaction. Compared to CRZ, there are virtually no complains to connected servers. Because you can join a guild with someone on an connected server. That's not the case with CRZ, so when blizzard wants more social interactions and CRZ, they need to go the full way: make servers only in name, connect all realms, get rid of the barriers of raids and guilds and voila, you have a better way to interact with somebody. You want to join with someone else for a group-content and then maybe join a guild because it was so nice to talk with them: sorry, but the others are in another castle. That's the big issue with content nowadays.
Do you know what is missing from all the points i wrote right now: NOTHING had to do with how you grouped up. Sorry, but it's quite foolish to think that even an automatic-lfg or lfr addon would destroy classic, it doesn't matter HOW you group up, the interactions LATER are important.
And yes, you can probably find friends easier in a dungeon that takes 1-2 hours instead of 10-20 minutes. And back then in vanilla, both was possible: for people who had enough time to clear the whole dungeon; you could even be in there for the whole Day (not rare in BRD) or you could simply kill fast a few bosses, skipping the optional ones; much faster than anything else. Heck, i talked more through toilet breaks with the group than i do nowadays. Dungeons that takes so long that a toilet-break is necessary; that's a reason why vanilla worked.
But to think that it's important HOW you group up is quite naive. That's why not even an automatic LFG mode could not ruin WoW (as long as the teleport-option is disabled). Not to say an LFG-Addon that has nothing of the automatic-options that an official LFG had.
Oh and another thing about classic in the end: Ilvl-comparison is also not possible in classic, since much gear that is BIS has actually a lower ilvl. And ilvl were not that much apart from dungeon to raid gear. In fact, i wished blizzard would simply get rid of ilvl, instead bringing back the brain-factor. That's also something that would not work in any kind of LFG-Addon.
Vanilla was so much more than spamming in any kind of channel to look for members.