I went to a serverless conference some time ago (great excuse to travel on the company's dime), and every single talk had a few minutes about how they were unable to test or debug their production infrastructure.

They couldn't even run their code locally, just bits of it. Serverless code could not run without a server. A specific provider's servers.

Call me old-fashioned, but I develop with a few docker containers locally, then release them to a plain old linux server, and it's working great. Sure, my humble business isn't Google, but neither are yours, right?