Agreed. It's not explicitly stated in the post but why would amount of experience (aka age) and Y-intercept even be mentioned at all if not to imply that more experienced people have a less steep slope.

I think this is a false axiom that young people have more potential. You actually have very low signal about people that age. They just went from a very structured context to a very unstructured context, so you may be assuming a lot from how they operated in the former context that may not be true now that they are in a different one.

This kind of ties in with another thread on here about OP being disillusioned with the skill level of their FAANG colleagues.