Mixing and matching a C(reate) or U(pdate) api call into a single request is exactly why its better. Logic can be checked, verified, confirmed, denied and rolled back.
Multiple entities with multiple endpoints are harder, if not impossible to enforce.
I disagree, pages for web apps don’t just CRUD one entity, they mix and match many entities in complicated ways. Also, I was referencing rails auto generated crud pages where there’s a single form and a single entity table.
If that’s all that’s required then kudos but rarely has that been true for the companies I work for. I wish it were true.