Originally Posted by
Murlocos
I'll give two reasons: story precedent for the faith-based classes and the unique cosmetics that come with them.
Blizzard has demonstrated attempts to showcase the diversity of paladins and priests as far back as vanilla. Priests had different racial abilities to showcase their differing faiths, when new paladins were introduced they were given lore to show how they weren't just interchangeable with Silver Hand paladins. Warlocks differ in this respect because their power source is universal: I think it's neat to play with how different races approach it, but they're ultimately all drawing power from demons and fel magic. A Sunwalker is not the same as a paladin of the Light is not the same as a Prelate of Rezan, and while game mechanics dictate they operate the same, Blizzard has constantly made efforts to differentiate them in the lore.
This has been acknowledged as recently as last year, when they added orc priest NPCs to Orgrimmar and they were originally just orcs in human clothing with names like Brother Shineblade. People rightfully pointed out how boring and lame this was, and they responded by completely changing them to be more orcish and writing new lore tying them to Nagrand and Oshu'gun. That stuff is cool! It makes the world feel more fleshed out and it's such little effort to dress up a few NPCs and write a few paragraphs of dialogue for them.
Druids aren't terribly different in that respect even if the current obsession with night elves keeps them closely chained to that specific racial fantasy. You have stuff like the harvest witches or the troll loa worship that differentiate them from the night elves. Wouldn't it be cool to see the unique way other races explored their ties to and worship of nature and the elements? That'd be so nice compared to like 16 instances of them all just being Cenarion students.
That's why the Tyr's Guard is so profoundly uninteresting, because they're all a bunch of different races that all act, dress and talk exactly the same. It's why the idea of all new shaman races being associated with Primalists in any way is so boring, because they're a total asspull of a villain faction with nothing distinctive about them except a slavish adherence to a 20,000 year old dragon grudge that they gave up after thinking about it for about 10 seconds. There's little enjoyable fantasy in these new groups because they're so one-dimensional.
Cheezits mostly covered the cosmetics point, but the fear is exactly that just going "oh they're all Tyr's Guard/Primalists/whatever" is what will lead to them missing the appeal of the classes in the first place. Nobody wants to see a paladins for all races headline and then see every new race just rides an Order Horse or whatever, nobody wants to see druids for all races and then see every new race just gets to share 5 new generic forms because "oh they were all taught the same way at Bel'ameth". That's why I at least don't like the idea of generic new lore to standardize these new race/class combos, because it suggests they'd want to do it by performing a quintessentially Blizzard blunder of answering popular fan requests but doing so in a way that totally misses the point of why people wanted it.
I know this is a long rant but I want to genuinely make the case for why this stuff matters rather than just rebuke. I'm not accusing you of it, but I've seen other people really push back against all of this and the argument seems to be that Blizzard should actively regress the depth and scope of how they handle worldbuilding compared to the past, and they should do it because it's not fair to expect Blizzard to care about anything that isn't humans, night elves, or cosmology charts. I can't understand it as anything but a reflexive lashing out at anyone that has any expectations for the game and doesn't just clap at anything Blizzard puts out.