This is insightful, thanks, but there's a little problem here:
The cost is borne one way or the other, the $500 is a matter of comp, not cost.
If someone is going to review your work, that's an act of very material labour. That they are not really compensated for it, at all, is inconsistent with the basic premise of labour and comp.
You would not be a researcher if you weren't comped in some way, so the absence and/or misalignment of comp is the issue.
It's not free to publish and have 2 reviewers (!!) there is a very material cost that you're just not paying.
Allocating at $1K cost for publication more accurately reflects the labour involved in checking it out (at least a little bit).
It'd seem to me a lot of folks might want to take up the $500/review as a job to earn some reasonable income, they might even get good at it.
It's entirely plausible that one of the 'dysfunctions' of science is 'not enough review' and it's simply because there is no incentive structure for it at all.
We pay people for literally every other function in life. Doctors are paid to 'save lives' even though there is a moral obligation. The notion that we don't pay people for academic work seems odd.
Perhaps journals could identify the papers with the most promise and offer payment for review, or something like that.