You could use gRPC responsibly, yes.
But the fact that it presents the remote resource in an API which resembles a local object means that programmers often get lazy in the manner of which they think about these things. The REST semantic is supposed to make this more explicit.
A remote object is not an object in your program or even your computer. It's something you're taking from something that is computationally miles and miles away. Compared to the microseconds it takes to dispatch a local call, it's an eternity away, even on a local network of the highest speed.
Accumulate those latencies over thousands of dispatches, and trouble can ensue.
I am reminded of an observation from when I first joined Google, coming out of their acquisition of the scrappy awesome ads company I worked at (Admeld).
We had a little service that kept track of ad impression caps / budgeting. We didn't want to serve an ad a single time more than the customer wanted us to, etc. Serving many thousands of ads per second, a process distributed across multiple machines in multiple data centres, this is a bit of a tricky shared state problem. The people who came before me had designed a rather clever solution which used a form of backoff to trickle down the number of ads served as they got closer and closer to budget cap, and to synchronize this state across clusters (this was before there were Rafty services to make this kind of thing easier, BTW).
We had a bit of a show and tell with Google when we first joined. I wanted to know how they were handling this problem, since their scale was many times ours, so I asked the question and got a puzzled/annoyed look:
"Oh we just make an RPC call to our budgeting server."
Summary: if you're at Google you don't have to worry as much about these problems. You still do, but there's an insane amount of infrastructure and horsepower and an army of SREs to help make it happen.
So, yeah, my point is -- just because Google does something or has invented something doesn't mean it's the best way to do it, especially in a smaller more cost conscious organization.