something with fewer restrictions is "not free." Not "not as good" but specifically "not free."
Frankly anyone who accepts this sentence as valid is a simplistic idiot, regardless of whether they agree with it or not.
The problem is the framing.
There's no such thing as a stand-alone "free".
There's alwaya a free to do something, or free from something, or free with regards to something.
Specifically with software, it's the freedom of the user to use it (for starers), then to study and modify it, and for it all to be meaningful, to share their work with others because modifying a realistically-sized software package is impractical.
Those are specific freedoms.
Whatever BSD gives, it's less of that than the GPL. It might give a different freedom.