Why do so many men do this? Over the years I’ve noticed when the conversation veers towards their wife, they usually say mean things in a “joking way”

This is a literal conversation I had the other day: Me: So how long have you guys been married? Dude: Too dam long LOL Me: oh really?.... Dude: Yeah lost count. Pretty much married her just to have a maid LOL!!!

I noticed this is usually only with wives, never have I experience this when a man is talking about his girlfriend.
Before I discovered this sub, I used to think this was normal behavior and just a “guy thing”. But now it makes me sad. It’s disheartening, there seems to be some kind of “I hate my wife” culture that a lot of men are a part of. And I’ve seen when they get together with other married men they laugh amongst each other about how demanding or nagging their wife is. Usually when I meet their SOs, they are so sweet and sound like great partners. And I doubt they say these things to their face.

Just why?