Intel CPUs backdoors use Minix (yes the one on the book and the one inspired Linux) not BSD. Routers, don't care. My routers are Linux. MacOS and iOS? They may be using pieces of BSD but from my perspective that's the BSD style death. You can't see the source code you can look at it you can't even be sure that it is really BSD. A OSS with BSD license tends to be sucked up the blood but nothing in return causing the OSS to die. Only exceptions are the ones born from big corps and supported by big corps like Chrome Android they are just big corps products.