In automotive talk, Tesla is usually shit on for their unavoidable low quality cars. (Because new) Maybe in 10 years serious car buyers would consider a Tesla.
I can't speak for this person's business, but profit margins can be slim.
This year my wife's company will have paid more money to contractors than she profited. Sure it was a "meh" year, but if she spent a few thousand dollars unexpectedly on IT, it would have erased her profit.
My point is that when you go out of your way to do things Free, it's because you couldn't afford the paid solution.
Back in my day, FOSS everything or you are an evil programmer. It's strange to see this was only a trend and now some nerds prefer locked down systems.
Few real world programming problems are straight forward enough to test on. Or at least I don't expect computer science to turn into a physics/chemistry/math level of science.
I think it's hovering around medicine. Where there is a seemingly art form to deal with the realities of our too complex biology.