I think that just proves his point. You're spending time doing the parts of the project that interests you.
Manufacturing PCBs isn't electrical engineering, it's process engineering. I'm sure there are some process-engineering hobbyists, so if people want to spend their time doing that, then cool. But his point is that if it's the electronic engineering part you're interested in, spending a lot of time tweaking and improving your DIY PCB manufacturing when you can order dirt cheap boards from China that arrive in less than two weeks, that are far and away better than what you could do at home, that generally isn't worth it.
Manufacturing PCBs isn't electrical engineering, it's process engineering. I'm sure there are some process-engineering hobbyists, so if people want to spend their time doing that, then cool. But his point is that if it's the electronic engineering part you're interested in, spending a lot of time tweaking and improving your DIY PCB manufacturing when you can order dirt cheap boards from China that arrive in less than two weeks, that are far and away better than what you could do at home, that generally isn't worth it.