As long as the GM is upfront about it before the game actually starts. A nice little email that says something like "Hey, I have an idea for a campaign. But there are no elves or druids for story reasons. Your characters will hopefully learn why as we play together".
That gives you some time to think about a character and maybe have a little back and forth with the GM about what you're playing. I would hate to show up at a table and five minutes before we're supposed to start find out that oh yeah, there are no elves. Redo your character.