Also, you can probably think about it like this:

"Will I benefit from this code being minimalist before [date]", where [date] is whenever you think the agent will be good enough to come back and make the corrections you would make today.

I'd caution that some corrections become harder to make over time, rather than easier. A bad architecture now can become much harder to fix once other things have grown up around it.

Even as a self-contained unit, you can't step in the same river twice, and on [date] some important details may have seriously faded, both in terms of text that can be mined and also in terms of human "why did we do that" and "what was the reason we did it this way and not that way" etc.