I would consider myself a person in favor of the ethical treatment of animals, and PETA campaigns like (the now quite old, but eminently memorable) "rebranding fish as sea kittens" [1] are so far out in la-la land, so ridiculous, and go so far in letting perfect be the enemy of good ("let's go after those unethical pescatarians!") that the organization loses credibility.
It doesn't help that in the intervening years, my main interaction with the organization (as well as Oxfam, ASPCA, etc) has been shady third party donation subscription hawkers trying to earn commissions off of tricking me into acknowledging them on lunch hour.
If there have been improvements in the treatment of animals over time, I'd make my own subjective leap to say they happened in spite of PETA, not because of it.