What possible value does a journal like Nature, for example, bring to the table by claiming a paper for themselves and charging people for it, given the alternative?
I don't see any value there. Maintaining an exclusive clique by using artificial scarcity while coasting on the dregs of reputation remaining to a once prestigious institution is what a lot of these journals are doing.
The world has changed. There's no need for that sort of pay to play gatekeeping, and in fact, the model does tremendous damage to academic and intellectual integrity. It allows people to get away with fraud and it makes the institutions motivated to hide and cover it up so as to not damage their own reputations by admitting anything slipped by them.
If you contrast the damage done by journals, with regards to suppressed research, gatekept access, money taken from researchers and readers alike, against the value they might plausibly provide, the answer is clear.
They're not needed anymore. The AI era, since 2017, has thoroughly demonstrated that journals are materially incapable of keeping up, that they're unable to meaningfully contribute to the field, and that their curation or other involvement has no effective practical value. The same is true for other fields, but everyone involved wants to keep their piece of the grift going as long as possible.
We don't need them, anymore. I suspect we never did.
