FAANGs are full of terrible programmers. It's obvious. What they do have though is a higher number of good programmers, and they try to leverage them as best they can to make use of the bad ones.
I hesitate to call them terrible. Developing is a hilariously multi paradigmed skill that is tough to train. Such that a good programmer may make a terrible developer, without the appropriate supporting team.
Similarly, an otherwise great developer can be horrible in a team that doesn't know how to use them.
Similarly, an otherwise great developer can be horrible in a team that doesn't know how to use them.