I don't see either side demanding anything. Each is providing conditionally free contributions. The article is one side explaining what they see as a downside to the other's conditions.
Well, to be fair, they did unilaterally assign their notion of criticality to this package and based on that unilaterally imposed conditions that the maintainer did not agree to up front and cannot negotiate.
One option would be for the maintainer to never release an update for their package on PyPI going forward.
The author also doesn't demand anything of anyone.
Users, on the other hand, demand Python software they want to use be available via PyPI. Since both PyPI and software authors are usually trying to act in some users' interest, there should be space for actual discussion and not this zoomer libertarian "nobody owes anyone anything" nonsense.
‘I think as the distributor of open source developers’ work, I can’t demand much from them’
The question is about maintaining a sustainable balance in the in-kind value each side perceives.