Dealing with PSP onboarding delays for small-mid market players

Anyone else finding the KYB process with major PSPs an absolute nightmare for anything less than enterprise-level volume? We're a mid-sized e-commerce operation, doing respectable numbers, but getting through compliance for new payment rails is like pulling teeth. Constant requests for documents already provided, weeks of radio silence, and then new hurdles. It's effectively bottlenecking our expansion into new markets and alternative payment methods. How are others managing this friction, or are we just stuck with the legacy providers who know us?