Meeeeeh, I'd rather this not be added.
Not following agreed upon host rotation rules would be better solved through some sort of automated host rotation option. I'm pretty sure there was a recent-ish request for that that might be worth reviving.
Host being afk could be solved by a time limit on choosing a map.
Host being a "troll" (you didn't list this in the OP but I'm including it as another reason I could see people wanting to vote host out) could be solved by being able to set restrictions on the maps chosen. I would be kinda sad to see that implemented because I could definitely see a few of my friends using it specifically to prevent me from choosing certain maps, but it could be used to prevent, for example, host from choosing atama no pony freeze [four dimensions] in a room in which no one can play them. Would also make it easier to find a multiplayer room you'll enjoy. Pretty sure there's also a request out there for this one. I personally wouldn't like voting host out to exist for this for those cases in which host isn't actually being a troll and just has different taste.
This request would help with multiple issues, but it's pretty crude and abusable and I'd rather we tackle the problems in other ways.