[headbee]

I see this argument made assuming that REST service creators are not aware of L3 REST but the fact that it never caught on is at least some proof of its ill-fitness to the general problem. Nowadays we have many more options that do what L3 REST tries to do (OData, GraphQL, etc) and most APIs at least conform to L2 REST. This is a classic case of friction between design intention and actual user experience: there was a push-door with a handle, and users aren't using the handle, they're just pushing it.