I think this might be about right. Google's internal tools were built by very smart engineers for use by other very smart engineers. (I'm thinking especially of the Producers Framework as I write this, but there are other examples.)

I've seen plenty of intelligent people struggle to get their heads around Google's abstractions. The tools are powerful enough, though, that once you get it you can pretty easily build stuff that scales to ridiculous levels.

It could be that better design will make these kinds of tools more accessible in the future.