Why I stopped using JSON for my APIs 8 months ago
My criticism is that protobuf is a premature optimization for most projects. I want to love protobuf, but it usually slows down my development pace and it’s just not worth it for most web / small data projects.
Distributing the contract with lock-step deploys between services is a bit much. JSON parsing time and size are not usually key factors in my projects. Protobuf doesn’t pose strict requirements for data validation, so I have to do that anyway. Losing data readability in transit is a huge problem.
Protobuf seems like it would be amazing in situations where data is illegible and tightly coupled such as embedded CAN or radio.