When writing these posts you have to be specific. What difficulty are you talking about? What level zerker are you talking about? How many players in-game (zed health scaling)? Map(s), if any in particular affect your argument? Are you talking about pub players or team players, returning KF1 veterans or new players? Etc. You have to remember that the devs are balancing classes for more than one difficulty level or class level. What might feel OP to you could be just right or sorely lacking in another setting.
I recently maxed out my zerker class to 25 after playing pretty much exclusively on hard servers, long games. I will say it feels like a very powerful class in the setting I've been using it. That said, I do not believe zerker is OP. I cannot just stomp over Scrakes. They're still dangerous. If I miss too many parries or get caught by more than one, I can die. Fast. Scrakes are not overly difficult to beat, but there is still a huge danger factor present if you approach them in the wrong way.
Husks, sirens, and bloats are still credible threats given the zerker's lack of precision ranged attacks. Crawlers are annoying to deal with. Stalkers are as well. A competent player can counter or power through all that, but most pub players (which are a majority of the people playing the class) are not capable of it even with the class's recent buffs.
Fleshpounds, interestingly enough, are a different story. Mostly I straight-up manfight Fleshpounds (i.e. trade blows without bothering to parry) because I can get away with it. This is not because of the zerker's strength, but rather because of a strange problem I've been noticing with FPs (on hard, at least) where if you crowd them or position them in a certain way, they bug out and go idle. You can get in a lot of free shots when they do this, and it only takes 5 heavy swings from the pulv to drop one in a six-player game.
I have not yet tried my maxed zerker class on normal, nor do I see the point in ever doing so. In that setting (i.e. maxed zerker on easiest difficulty), the class would definitely be OP. However, I also have not tried zerker on Suicidal or HoE. I suspect that it will still be very powerful on those difficulties, but also very vulnerable to being overrun without proper support (a medic to heal or a commando to kill sirens/bloats/husks, etc.). It would be a glass cannon, if you will, and totally fair in my eyes.
Here is the bottom line for me when it comes to altering the zerker class further: I LOVE the way it feels when I play it. It feels good. I feel powerful when I swing my Zweihander. I enjoy the feeling of catching a horde of clots with my shovel. Pulverizer explosions in zed time make me happy I bought this game. I also like how 200 health doesn't save me from death if I'm not careful. I have to pick my fights. Two scrakes with four sirens behind them and a horde of clots? Can't power my way through that. Two husks taking up their shooting stance with me not close enough to kill them? Better dodge/take cover before running them down.
What most people forget when complaining about the zerker is that the zeds don't have to kill you to beat you. They just have to get your health low enough that you start running more slowly. For a zerker, movement speed is life. Losing speed is death. The extra 100 health doesn't help all that much in this regard, because the movement penalties for losing health are based on a percentage, not aggregate health remaining. Zerkers are plenty vulnerable without any additional nerfs. If you don't think so, you not playing on a high enough difficulty or else you're not taking into consideration that other players are not as good as yourself. I could understand some tinkering with the zerker's stat bonuses (seriously, the attack damage modifiers get insane by lv. 25) but I really hope TW doesn't change the class too much if at all.