Yes, the potential is there, I've seen bigger accounts go out of their way to downvote smaller accounts due to retaliation, some even just cause they were following a downvote trail and I can tell you I've done what I can to counter that and get in the way of such activity. Someone named kingscrown used to do this because he'd go out of the way to receive another cent on his posts and his intentions were clear for a long time and thanks to downvote mana we were able to finally fight him off and his ways of retaining that position.

So while retaliation exists, it doesn't mean everyone does it or that people should be afraid to use their downvote mana. I'd welcome it on my posts they feel are overrewarded though I'd prefer they knew more about the author and the value he might bring or at least tried to bring to the ecosystem before doing it compared to say random authors who just post, engage a little and go on about their day receiving a to of rewards that could've made the day of 6 other minnows instead who put in just as much time onto Hive as them.