I misunderstood your post, I thought you were blaming stripe.
I agree with you though there is sometimes value in payment gateway aggregators. Having one for managing multiple processors, including payment methods stripe doesn’t support.
Stripe itself is a payment processing aggregator: you could just implement the direct integrations from the banks/card networks.
But yes fintech is built on middlemen building on top of middlemen. Sadly it’s too expensive to build from the lowest layer, so businesses tend to start from the highest one and only rebuild a layer below if they’re successful and have money.
It’s only fixable with more open source fintech layers imo.