It could lead to a mess, sure. But my favourite prompt on an LLM-untouched codebase is along the lines of "find UB and other bugs. If the fix is less than 5 lines, fix it and commit it. One change per commit". Then I of course check the commit history before pushing.

My experience over the last couple of years with this type of prompt is that eventually you run out of bugs to find (meaning you reach "I see what you mean, but I disagree").

And those fixes don't cause messes.

And a new model may find something new, but not even remotely the volume seen the first time. This indicates to me that the supply of bugs is finite, and after this period of house cleaning, it should go down.

But anyway, a mess (decoherence) doesn't necessarily mean an exploitable mess.

Reading that good article, I find myself thinking that we did not need LLMs to get decoherence in complex software or systems. At least LLMs don't have personal fiefdoms, egos, and company politics adding to encouraging decoherence.