Some people love it. I had an uncle who was like that with his coworkers in construction; constantly teasing and criticising (and coworkers giving the same right back). Many people would think they were fighting, but they were the best of friends and enjoyed the repartee.
Some might call it toxic, and it wouldn't be allowed in a corporate environment today, but clearly no environment will please everyone. For them, it was good.
True, on paper sounds horrible but it's not done in any kind of vindictive bullying manner or in a jock locker room way. New hires feel more confident communicating instead of panicking and not telling anybody. Code quality attacks like OP described don't come off as personal, so nobody is silently seething because they've been offended. It eliminated all bs notions about work place 'teams' when in reality we're competing with each other every day for more recognition, bonuses, promotions. Everywhere else I worked people did this anyway but behind other's backs, which to me is truly negative and a shitty dysfunctional work environment. The latest new hire said this was the only office where there was no anxiety of coming to work because fucking up wasn't the end of the world anymore.
Some might call it toxic, and it wouldn't be allowed in a corporate environment today, but clearly no environment will please everyone. For them, it was good.