Except GPL doesn’t say, “keep it free”, it says “keep it GPL”. Public domain is also free, but GPL’d code cannot be made that, except by the original “licenser”.

And while I can’t speak for other countries, the USA’s copyright regime, which is what would be relied upon to actually enforce the GPL in the US, is entirely built to serve business interests, which makes the GPL’s actual utility in enforcing “freeness” of software dubious at best.

GPL doesn’t give the original owner any power over others it just requires the code which was born free to stay free.

In the US at least, this is untrue; the only entity with legal standing to enforce (via lawsuit) the GPL on a piece of software is the creator(s). Obviously as GPL ‘flows’ through redistribution, that becomes more nuanced, but it’s always limited in standing of who “owns” the improperly-redistributed version. That is absolutely power that is unique to the ‘owner’ of the software.

GPL is bad because it perpetuates the concept of durable intellectual property ownership/ licensing over supposedly “Free” (as in libre) code. Durable licenses are all bad. Unlicense is the only true FOSS license in common use, with an ‘F’.

“Free, but you must do these things” is not actually Free.

Notable and very honorable examples of projects that use Unlicense are youtube-dl and yt-dlp (and obviously, those are not programs intended to benefit corporations).

Now you have heard an argument against GPL that is not about corporations.