APIs are toll roads. If you need an API key just to read a price, it is not the Open Web. It is a walled garden. We designed this to be permissionless. A text file has no gatekeeper. It bypasses the rent seekers entirely. The standard must belong to the commons, or it becomes just another extraction layer. Keep fighting the good fight.
I'm working on a Shopify alternative[0] as part of this decentralized marketplace. If adding support for CommerceTXT is not too difficult, I wouldn't mind adding it.
0. https://github.com/openshiporg/openfront