TBC zones, no, you didn't get to Honored (required for heroic keys) just by doing the quests in the zone, nor was it as simple as running a dungeon few times. Was a teensy bit longer to access heroics. Gated. Oh but grinding a dungeon multiple times for a little bit of rep was meaningful to you apparently.
Raids: as I said Karazhan was about the only one which you could finish in a day, I guess assuming one person in your group has a key to all the 5mans required for the quest line...early on, yeah good luck finishing it in one day. lol.
SSC required some 5man, Kara boss and some other raid boss. If your raid group is all on the same page, I could see all those being done in one day....albeit, an enormously long day. Gated.
TK would never happen in a day, I still shudder at that chain. Very Gated.
Hyjal required rep + T5 end bosses. If you did this before they allow people to bypass all other bosses, you'd know it wasn't a days work. A week, sure. You got Gated.