> Open-access publishing implies the authors are paying the cost of publication and its popularity in STEM reflects an availability of money

No it implied the journal not double-dipping by extorting both the author and the reader, while not actually performing any valuable task whatsoever for that money.

> while not actually performing any valuable task whatsoever for that money.

Like with complaints about landlords not producing any value, I think this is an overstatement? Rather, in both cases, the income they bring in is typically substantially larger than what they contribute, due to economic rent, but they do both typically produce some non-zero value.