there is quite a lot of funding
> often paired with too much bureaucratization (selection processes that look at "objective" and "verifiable" metrics
this is the problem.
The whole OP reads like a bizarre hit piece on open access. How could scientists paying to publish their work incentivize them to publish more? How would spamming the world with more publications inflate a scientist's impact factor? (It wouldn't -- impact factor would be diluted by the spam)
It was always possible to self-publish and to cite self-published work, and even without journals, a modern scientist can publish on a free webhost for even cheaper than an open-access journal.
I assumed that the point was that the journal is incentivized to publish as many articles as possible, and hence to lower review standards.
If you're just charging for publishing articles, you don't care about whether anyone reads them or about what your "prestige" is, since you don't make any money off of that.
It's true that if I publish a paper it's better for me if it's read and thus cited, but that's much less of a difference compared to published vs not published at all. The entire problem starts with authors not being incentivized to publish a few good articles over churning out as many as possible.
While I often bash for-profit journals for being parasites that do little actual work and profit from withholding access to science that should be public, and for this I would open a bottle of champagne if they disappeared, I don't think journals have much to do with this particular problem of incentivization of bad science. Journals just respond to the demand of publishing more, and shallower, papers. That demand comes from hypercompetitivity in academia, where researchers need to fight for scarce positions and scraps of funding, often paired with too much bureaucratization (selection processes that look at "objective" and "verifiable" metrics like number of papers published at a given impact factor quartile, etc., instead of just asking a bunch of neutral experts whether the person is doing good research, which may be more opaque but also much more meaningful).
As evidence that journals are not the problem in this particular case, in fields like machine learning, where publication happens mostly in arXiv and conferences that don't charge for publishing or reading papers, the problems pointed out in the post also exist. Published models that only beat previous ones because they were lucky with random seeds or data splits are widespread.