It might just be me, but AI has made my code more human-maintainable. They've been complaining about obsolete comments, separation of concerns, testability, global mutable state...

(Also performance and security issues, addressing which doesn't make the code more readable, but does make the program itself more robust.)

That being said... I have found them weirdly unsuitable for some tasks though, e.g. asking frontier LLMs to assist me with game development, I found that they were not able to add simple features to a simple Pong clone (nor even port a working Pong implementation) without constantly breaking things. (Yes, Pong, from 1972!)

So, I want to say YMMV, but just the past 2 weeks, my own mileage has varied very much! They seem to be extremely domain specific.

"Half the time, it works every time!"