And obviously employee count shouldn’t scale linearly with user count. No idea where you get that idea?
To argue that a 1B+ user app of moderate complexity can’t be run by a few hundred employees is simply wrong.
The end game for all web software is going to be managed services with automation built in such that it requires almost no manual intervention (absent logic bugs). This gets easier and easier to accomplish as cloud capabilities grow. And cheaper.
The long term trend for tech is obviously towards fewer employees and bigger impact per employee through leveraging higher level abstractions. Look at what you can build as an individual today vs 20 years ago and it’s quite obvious. Unless you think technological progress will suddenly halt