One thing I think that is important to point out is the, “working beautifully” part. I agree that rewriting stuff just because is a waste of time and money. There are plenty of solutions out there that may solve a problem and may be working fine, but have now hit their scaling ceiling and people become frustrated. Rewriting stuff is a part of software, but should almost always be done incrementally.

I also don’t think it’s laziness. Developer hubris is real and it can get in the way of actual business value.

You pretty much nailed everything else. I share the sentiment because I’m currently working on splitting up a monolith into microservices. Most of the “quick wins” are things that didn’t need to be rewritten anyway, and the stuff that actually sucks is difficult to address. It’s tricky to get right.