dont be disingenuous. they primarily get paid off the net interest margin between the cash i deposit and what they loan out.
The fed, fdic and occ all maintain a variety of a&l rules that outline what categories of loans can be approved that range the gamut from in state/out state to subsidized loans/market rate loans. Thats before taking into account all the consumer protection frameworks.
All that is to say, if a bank gets to a loan/deposit ratio above .9 they are likely considered insolvent depending on the framework in question. The reserve requirement is no brake on their ability to loan out deposits, but there are lots of other ones that apply.
I think the thing that actually moved the fed to remove the reserve requirement was the big banks sitting in the 50-70 range (and of course the covid liquidity crunch). The monopoly we grant banks is in part so they will finance economic activity, if they aren’t doing that we’ve got a structural problem.