I don't think companies would flock to NetBSD. They'd do what you see with FreeBSD: rip out the parts they like (typically the TCP layer) and repackage it into something unrecognizable (Wii's OS, PS4, etc.) That's specifically the embedded space. Linux did well in the desktop and server space because of driver support more than anything, and it came up before the VM farm (a.k.a "cloud") era.

It's been a long time since I looked up the Tivoization/GPLv3 debate. What would have that license done in modern terms? Would we not have linux-firmware? Would Android still be just as annoying to make custom ROMs for? You could make the argument then we'd see fewer binary blobs and less need for things like coreboot ... or companies would have found more interesting legal ways around those limitations.

As far as Linux foot-gunning themselves more these days, there's the whole zfs/write_cache_pages thing with the kernel 6.18:

https://www.phoronix.com/news/Linux-6.18-write-cache-pages

although it looks like one dev already found a work-around:

https://social.lol/@robn/115189135969338619