Why BSD?

Because the BSD license allows binaries to be distributed without also distributing the code.
The BSD license is friendlier to companies that want to add proprietary changes to the code
without having to release them for their competition to pick up for free.

There are many many people who hate the BSD license for this, and many many who despise the
GPL for not having this.  Regardless of that particular flame war, that is the difference, and
that is why the BSD license *in this case* is seen as a poison pill to keep the code base
under the GPL.