It was always possible to write large amounts of crappy code if you were motivated or clueless enough (see https://github.com/radian-software/TerrariaClone). It's now just easier, and the consequences less severe, as the agent has code comprehension superpowers and will happily extend your mud ball of a codebase.

There are still consequences, however. Even with an agent, development slows, cost increases, bugs emerge at a higher rate, etc. It's still beneficial to focus on code quality instead of raw output. I don't think this is limited writing it yourself, mind - but you need to actually have an understanding of what's being generated so you can critique and improve it.

Personally, I've found the accessibility aspect to be the most beneficial. I'm not always writing more code, but I can do much more of it on my phone, just prompting the agent, which has been so freeing. I don't feel this is talked about enough!