My guess is you missed the point of Free Software. Anyone can use it in any way, including selling for profit. "Free" as in "freedom", you know

Recently I created a small homepage with different re-packaged versions of Java: https://jdk.dev

All that alternative packages are free of charge but they have extended support from a number of big companies. All these companies funded separately, there's no common place for donations or something.

That's totally ok in the world of Free Software. Pick any source code you want, repackage, rebrand it, sell it as you wish and may the Force be with you. People do it all the time.