Yes, but probably a business opportunity to write an API layer over the top, that writes files and SFTPs them on the backend. Sadly.

Only if your business is "writing files in plaintext and SFTPing them." Payers are basically immune to technical disruption, and it's really not worth the effort trying to create friendlier facades on what are essentially 1960s-era business and EDI processes. Someday they'll catch up technically, but until then med-fin-tech startups are punching boulders uphill.

Do I sound bitter? I think I sound bitter.