Earlier quoted context omitted.
Meta makes websites and apps. Historically, they haven't succeeded at lower-level development. A somewhat recent example was when they tried to make a custom OS for their VR headsets, completely failed, and had to continue using Android.
You're generalizing a failure at delivering one consumer solution and ignoring the successful infrastructure research and development that occurs behind the scenes. Meta builds hardware from chip to cluster to datacenter scale, and drives research into simulation at every scale, all the way to CFD simulation of datacenter thermal management.
They have the money and talent to do it. As you point out, they do have major successes in areas that take real engineering. But they also have a lot of failures. It will depend how the internal politics play out, I imagine.