That has not been my experience. The issues are with licenses other than BSD but that's the same in Linux; Linux can also use BSD code, a lot of Linux code is actually dual licensed as BSD already.
It’s not - Linux does have problems with licenses which are incompatible with GPL, such as MPL/CDDL. BSD doesn’t, because you can’t have license incompatibility without throwing GPL in the mix - it’s the only Open Source license that can be incompatible with others.
FreeBSD does avoid pulling restrictively licensed (closed source or GPL) code into the base system itself, but a Docker port would be third party (ports/packages), not the base system.
Not really, with Linux it's the same as it would be in BSD if they wanted to avoid conflicts with GPL. You put that code in an optional module and have the user compile it. I am unsure as to why BSD people seem to think that using BSD means you can avoid problems with the GPL, if you use any GPL code for any reason (and there's a lot of it) then you have to pay attention to these things. If you insist on only running BSD and CDDL code then you can avoid it, but that's going back to putting politics over software again, the kind of thing that you were saying you were trying to avoid.
Also, it’s not politics - it’s mostly just that the old GNU cruft is being replaced, and newer, better solutions prefer more liberal licensing, see GCC vs LLVM.
