My players are totally fine with restrictions. I ran a multi-year 3e campaign for them where I removed/replaced all the standard PCs races other than human. I got not one complaint.
That said, I don't usually place restrictions on players. Other than, "find a reason you all adventure together".
When it comes to mechanics/class options, we have an agreement. I'm not going to ban anything outright --that would require a lot of tedious vetting of material-- but if something becomes a problem for me during play, we're going to fix it. And that might mean 'nerfing'.
When it comes to more... aesthetic choices, I try to give players their say, so to speak. My evolving view on this is pretty simple. I've removed classes and races from my settings for aesthetic reasons in the past. Creative editing can be important. But, I've found editing alone can't get you a interesting fictional setting, and mistaking editorial control for creativity is a mistake.
Which means if I remove elves from a setting, but a player *really* wants to play an elf (or half-orc, or gnome, or a Confederate veteran who was the victim of wanton, accidental teleportation), I'll probably accommodate them, as long as the player is willing to run a PC without ties to country or culture. That way, I get my creative agenda and they get (a tiny amount) of theirs...
Any campaign setting I design/run is going to have a staggering amount of me in it, for better or worse. I can afford to cut my players some slack, even when they make aesthetic choices I don't particularly like. Besides, if running the campaign is so unrewarding, overall, that a player's choice of race/class is such an irritant, then I should graciously step down and let someone else DM.