Sorry, in general that is not true. You need a very good network connection, both with bandwidth and latency, to make remote devlopment workable. Still, it never equals local development. If you follow the discussions here on hacker news, which terminal software has the smalles latency, remote development never can compete with that.

Apparently having UNIX servers on premises is a forgotten art.

It is. Even if companies have their own hardware, it is often in separate compute centers. And of course anything on AWS or Azure is not on premise.

Not everyone is FAANG, or pretends to be one.