Mu.
There are fundamentals of the setting and there are accidents of the setting. The fundamentals need to be kept, the accidents don't.
For example in Krynn (as you mention between the Cataclysm and the first novel) it is a huge plot and worldbuilding point that there are no true clerics. No clerics is right there in the elevator pitch.
Meanwhile, with the arguable exception of dragonborn it is an accident of the setting that there isn't a weird tribe of orcs somewhere in the mountains, or a couple of halflings somewhere or granddaddy sold their soul and so we have a tiefling.
Yeah, this is what I think gets lost in all this. How many of these constraints actually matter beyond "I read it when I was 12 so now it must be so"?
Like the no clerics thing? Important to the setting of Krynn before the start of the war. No orcs? Never really matters in a world with goblins and hobgoblins and such.
I tend to think that many folks focus way too much on the unimportant elements, and they do so out of some kind of nostalgic attempt to maintain lore.
In my experience the main creativity fostered by constraints is the creativity in subverting the constraint. And the more constraints you put out there the more peoples' inspiration and attention is going to be grabbed by seeing how they can subvert those constraints.
If you want people inspired by your setting point to that which is inspiring and treat them like adults. If you bang on about how "we shall have no wizards and arcane magic is feared, and no clerics because the gods are dead" then you'll get the situation I saw at one Dark Sun table where there were no wizards ... instead there was a bard, a pact of the tome warlock, a druid, and a paladin. Because every player had their inspiration grabbed by the restrictions.
It does tend to be an immediate response. Can't do this? Well what if...?
It's that creativity everyone's happy to mention but not exercise.
Yeah, people spend a lot of time trying to get out of constraints rather than accepting them. I'm not sure how creative it is to be told "no" then knee-jerk fight against that. It's a common reaction, yes, but it's not particularly creative.
I think the point was to focus on what's interesting about the setting... what cool things the players can be, rather than to start off by telling them what they can't be.
Also, maybe I'm weird but "treating people like adults" includes expecting them to follow the rules they agreed to and not whine about it. Setting up a game with constraints then having players rail against those constraints is functionally identical to a player complaining that they're out of spell slots and should get more. Sorry, you agreed to play this game and here are the rules you agreed to. You agreed to limited spell slots when you created your caster character just like you agreed to no orcs or clerics when you agreed to play this Dragonlance game set between the Cataclysm and the novels.
Labeling one side in a disagreement as "whining" doesn't really do anything. We can just as easily say that the DM can stop whining about their precious setting.
As has been repeatedly said, the best solution isn't to accuse either side of whining. it's to talk things out and find a reasonable solution.
It's also why, given the limited nature of the poll where there is an actual conflict between lore and player options, I go with players... because lore is make believe and players are real.
Who gets to decide what's "dull and basic"? You?
Yes.
I like how they act like they don't have halflings because these halflings have topknots.
Ooo what if the halflings were annoying rather than rustic?!?! Genius!!!!