So, reading this the other way (browsers are king)... you claim gRPC is so useless as to not be able to power your entire system and requires you to standup duplicate interchange systems for different use cases?
Yikes.
I also have a tendency to consider that Envoy proxy to be more of a feature than a bug, anyway. It's pretty easy to set up, all told. We want to gatekeep the edge, anyway, for various reasons, so it's not like there was ever a reality in which we weren't going to be fussing with a reverse proxy. And it serves as a nice opportunity to stop and be thoughtful about exactly what we're choosing to expose to the Internet.
Speaking purely as a developer, I do find it to be an annoyance. But I also acknowledge that inconveniencing developers for the sake of the greater good can be a wise move.