The BSDs fall into the class of server/desktop systems. They would be a great choice for certain classes of products (e.g. routers) where there exists strong feature alignment, but not something I would consider suitable for producing my usual minimal custom embedded systems.

Generally, esoteric hardware support also will be better in Linux, so BSD would likely require porting or writing more drivers when bringing up a custom board.

That said, BSDs have not my strongest area, so I would be curious to see others’ experiences and opinions.