As a player, I want a set-up that sounds fun to adventure in. If it sounds fun but has limits built in that go along with that fun theme, then that sounds fine. (It's fantasy take on a real country, it's a riff on this novel, it's a riff on this novel but I swapped races, it's a 5e version of this 1e setting, it's a land that has gates to many worlds, whatever....). Once I hear the pitch, I'll start thinking of characters that sound fun to use in that setting.
As a DM, if I have an idea for what I'd like to do then I make a pitch and the group is either good with the pitch, has some suggestions, or isn't interested. Once a pitch is accepted I'm always happy to work with a player who has an idea that doesn't exactly fit but is in the spirit of the set-up. Similarly, as a player, I like it when a DM is open to modifying a class or race a bit to allow something that seems to fit the world they've described - but if I've agreed to the pitch I wouldn't ask for something that went against the spirit of it.
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I always wonder if folks who don't like any restrictions on race or class or whatnot would be fine if I showed up playing an arbitrary level too. I mean, the rule book has rules for starting at any level, why is my being 15th when everyone else is 1st any worse than my being a wizard in the non-magic world? (One of the first big game I played in had lots of deaths, always started new characters at 1st and had a wide range of character levels -- so it's not like the game can't work in that case.)
On the other hand, the "I just don't like <insert race here>" kind of restriction does make me want to play that race a bit... even if I wouldn't push for it.