Just to clarify, vultures are no birds off pray, they eat things that are already dead.
I don't think they should attack players, but instead fly away when you get to close, before starting to circle around your head. They'll keep doing this untill you are to far away, jump in water, attack them, or find another creature to follow, kinda like parrots, or they just get bored after 3 days or so.
If you have rabbit meat out, they'll land, and you can tame them. Tamed vultures won't be distracted by other creatures and keep following you at all times. If you stand still they'll also land and you can order them to sit down.
This is fun and all, but a mob needs a use. Either they help you, provide you with resources, or kill you. A mob can't be just for aesthetics, like the bat or polarbear, which main goal is too look good and attack you only because it's realistic. how does this apply to the vulture?
I think it'd be a great addition if the vulture would fall under the help catagory.
They can be used to track other creatures, since they'll circle above all animals and mobs, and you can now spot them from far away.
Their main use is when they are tamed however, since, as I said, vultures are scavengers and only eat dead things, as well as undead things. Knowing this, we can put it to use. Both tamed and wild vultures will attack zombies, like you've described, but tamed ones will always be at your side to protect you, so taming them is a good idea.
As for now, the desert biome is an absolute waste, and with the inclusion of husks, the developers made it clear they wanted the desert to be a place people rather walk around. Adding vultures that attack husks and zombies will make it so that the needed protection from daytime zombies balances out the lack off cover, food and building material. Deserts will get a use again, be it just to tame birds and get out.