Animals have a tendency to dislike you. You suffer disadvantage on all Animal Handling checks. Additionally beast type creatures prioritise you as a target in combat (as long as doing so does not put the attackers in some obvious additional risk).
FLAW. This is a flaw feat. At your DM's discretion, you may take this feat at level 1. If you do, you may also gain a feat, or increase two of ability scores by +1 (or one by +2).
honestly, this seems like nothing but a benefit, finally a way to do a proper tank build (due to the lack of agro-drawing abilities like in most (video) games where "Tanking" is a role), even if it only works against beasts
Sounds great until your level 1 tank has 4 wolves attacking him and you get hit by 4 attacks and die because they all have advantage from pack tactics.
Sounds great till you're walking through down and you can't go buy your item from the store because the shop owner's dog growls and barks loudly at you, and the owner trusts the instincts of their beloved pet.
Sounds great until the horses you paid for to make your treck across the countryside won't let you mount them and get spooked by you.
There are a lot of ways for this to go bad and be a negative. It's only a pure positive if your DM ignores/forgets about it.
That's the entire point of this "feat". It isn't. It's a flaw. Something that changes how you play the game. In addition, if you're having all of those problems with this flaw, then the DM needs to chill out. Yes, animals don't like you. That doesn't mean they should get aggressive or scared as soon as they see you. Weary, sure, but not outright hostile.