The reasons for that line get at a fundamental tension. As David Wheeler famously said, "All problems in computer science can be solved by another level of indirection, except for the problem of too many indirections."

Over time we accumulate cleverer and cleverer abstractions. And any abstraction that we've internalized, we stop seeing. It just becomes how we want to do things, and we have no sense of what cost we are imposing with others. Because all abstractions leak. And all abstractions pose a barrier for the maintenance programmer.

All of which leads to the problem that Brian Kernighan warned about with, "Everyone knows that debugging is twice as hard as writing a program in the first place. So if you’re as clever as you can be when you write it, how will you ever debug it?" Except that the person who will have to debug it is probably a maintenance programmer who doesn't know your abstractions.

One of the key pieces of wisdom that show through Google's approaches is that our industry's tendency towards abstraction is toxic. As much as any particular abstraction is powerful, allowing too many becomes its own problem. This is why, for example, Go was designed to strongly discourage over-abstraction.

Protobufs do exactly what it says on the tin. As long as you are using them in the straightforward way which they are intended for, they work great. All of his complaints boil down to, "I tried to do some meta-manipulation to generate new abstractions, and the design said I couldn't."

That isn't the result of them being written by amateurs. That's the result of them being written to incorporate a piece of engineering wisdom that most programmers think that they are smart enough to ignore. (My past self was definitely one of those programmers.)

Can the technology be abused? Do people do stupid things with them? Are there things that you might want to do that you can't? Absolutely. But if you KISS, they work great. And the more you keep it simple, the better they work. I consider that an incentive towards creating better engineered designs.

I think you nailed it. So many complaints about Go for example basically come down to "it didn't let me create X abstraction" and that's basically the point.