Just look, for instance, at FPGAs: almost all the tooling is proprietary, very expensive, and very buggy too. Or look at PCB design: Altium seems to be the standard here still, despite Kicad having made huge advances and by most accounts being as good or even better. It took decades (Kicad started in 1992) for the FOSS alternatives here to really catch on much, and only really because PCBs became cheap enough for hobbyists to design and construct their own (mainly because of Chinese PCB companies), and because CERN contributed some resources.
I'm not sure what the deal is with engineers hating collaboratively-developed and freely-available software, but it's a real thing in my experience. It's like someone told them that FOSS is "socialism" and they just reflexively dismiss or hate it.
Well if you're dealing with projects worth 7 figures (or more), it absolutely makes sense to go for a commercial project with SLAs on support. Last thing you want is to hit some showstopper bug, holding up people who earn 4-digit daily compensation, and been told to "figure stuff out yourself".
If you as the author of a FOSS project that isn't a household name already for historical reasons (like, say, OpenSSL or cURL) and you want it being used by anyone else than hobbyists and universities, you won't get around establishing some sort of corporate infrastructure to sell support contracts.