It isn't about selfishness or entitlement. Every single person playing this game is paying for the same access, and has exactly the same amount of freedom to do whatever they want while they're online. None of those people are obligated to give up playing so anyone else can, and to be blunt it isn't up to anyone else what they're doing with that play time - the only people who get to dictate that are Square Enix themselves (beyond obvious things like, y'know, not doing things that break rules or are illegal. Obviously.)
Sure, kicking everyone periodically gets the queues moving and shuffles who's online, but basing it on an entirely arbitrary time limit like what OP suggests doesn't make the queue problem actually go away. Especially not when there are so many errors and issues with the queue process itself. Sure, some people are waiting an hour or less and getting in no problem. Others, on bigger servers though? Not so much. It took me three and a half hours to get into the game on Saturday. I got into the queue at 430, and 2002 errored out of line no less than six times over the course of a 5k+ player queue. And that's only counting actually getting kicked, not the additional 2002 errors trying to get back in line - because I also lost my spot in line once due to getting six (yes 6) DC's in a row just trying to get past the title screen. I didn't get to start playing until after 8 pm. So yeah, if I don't keep playing and playing and playing until I'm literally sick of it, then me logging off anytime after 2 pm means I am not playing again at all that day.
Honestly I'd be more okay with them doing periodic server restarts or something. I vaguely remember them doing that for Stormblood. At least then it's just a blanket reset for everyone instead of "you are specifically only allocated x hours regardless of what you're doing or who you're playing with"
I'd love for them to do something more to make this situation less frustrating, but I'd frankly rather wait for the servers to chill out naturally than deal with a forced limit on how long I can play the game.