Quality code is easy to make changes to. What makes terrible code terrible is that changes become harder and harder to make over time. LLMs haven’t solved this, but the marketing acts as if it has, and many engineering orgs seem to have instantly forgotten the things we’ve learned from the last few decades of building software.
Yes you can have your agents do refinement and refactoring. If you don’t know what they’re doing when they are doing that, they can and do introduce massive churn. The “build it fast and fix it later” crowd seemingly has never had to actually go try to fix it later, or dealt with production incidents when people have no idea how their code works. These folks are frequently promoted fast for their “productivity” and massive promises by clueless management and move on to let others have to clean up their stuff.
Yeah I expect we're going to see a lot more "disposal code" vomited up.