All kinds of worries are possible. (1) It turns out that all this AI generated stuff is full of bugs and we go back to traditional software development, creating a giant disinvestment and economic downturn. (2) sofware quality going way down. we cannot produce reliable programs anymore. (3) massive energy use makes it impossible to use sustainable energy sources and we wreck the environment every more than we are currently doing. (4) AIs are in the hands of a few big companies that abuse their power. (5) AI becomes smarter than humans and decides that humans are outdated and kills all of us.
It obviously depends on how powerful AI is going to become. These scenarios are mutually exclusive because some assume that AI is actually not very powerful and some assume that it is very powerful. I think one of these things happening is not at all unlikely.
1 and 2 are really only an issue if you vibe code. There's no reason to expect properly reviewed AI assisted code to be any worse than human written code. In fact, in my experience, using LLMs to do a code review is a great asset - of used in addition to human review