My understanding is that FreeBSD freezes its kernel ABI for each major release and this enables third-party drivers to be written against it and supported for t

My understanding is that FreeBSD freezes its kernel ABI for each major release and this enables third-party drivers to be written against it and supported for that major release. There are out-of-tree graphics drivers in the ports tree making use of this today. Both AMD and Nvidia drivers from what I can tell. Other non-graphics drivers as well. A freeze for a couple of years seems like a reasonable compromise to me. It's not forever, but it's long enough for third-parties to develop, validate and support a product for. The closest Linux gets to this is vendor kernels which are both vendor-specific, and highly-custom and badly dated. This at least gets you something reasonably current and supported to work with.