I release my code as open-source because I don't want my end users to ever end up unable to fix bugs in the code they're using. I don't want my code used in something like macOS where users are stuck using what they're given; it might help those users in the short term, but I believe it leaves them worse off in the long term.
By analogy; if one is free to rob someone, they're more free in absolute terms than they're free if they can't do that, but then the person who is about to get robbed isn't free to feel secure. So in other words, the robber is more free, but at the expense of the robbed.
In that sense, the BSD license is more absolutely/selfishly free for the individual, whereas the GPL is more freedom-perusing for the entire community.
Was that the point of free software? I thought that the point was freedom: that users be permitted to use, modify & redistribute the software they use. Inclusion of BSD-licensed code in proprietary software fails at that: a macOS user is unable to use macOS without paying for it; unable to legally modify it; and even if he did modify unable to legally distribute those modifications.
BSD-licensed code is awesome for vendors of proprietary software who want a head start; it's not so great for users.
The first step of making useful software is by having users. If nobody uses your software because of licensing reasons nobody will ever contribute to it and it might as well not exist. On the other hand if there are users then there is a chance that a subset of the users will contribute back voluntarily.