> No, the point of permissive licenses is that third-party derivatives, which have no impact on the licensing of the original, don't have to be free ever, while the point of copyleft licenses is that they do.
This should read "Yes, [...]".
The point of permissive licenses is for people to sublicense it. You can use this to sublicense the software using a license that actually enforces it must remain Free (see Redict for an example) but it is almost always the case that someone uses this headlining feature of permissive licenses to lock the code up and extract rent.
Your next paragraph frames single contributor or CLA as the two primary development patterns, when that those are absolutely the exception, especially if we exclude repos for things like AoC our homework, which are mostly single contributor.