Do you have a definition of “actual software developers”?
To me an “actual software developer” is always learning, always growing, always making mistakes, always looking back and blown away by how far they’ve come - and most importantly, is always willing to generously offer a hand up to anyone who cares enough to learn the craft.
It’s ok to make a big ball of mud! You can deal with it later once you understand the problem v1 solves. Parallel rebuilds and migrations are part of software engineering. Or alternatively - maybe that big ball of mud does its job, has no new requirements, so can be left quietly chugging along - for potentially decades, never needing a v2.
I think they just mean professional who's responsibility at the company is to code. There are a lot of professionals that do some coding on the side of their main role, but it's not their responsibility to look after the code for 8 hours a day.