There is a huge pool of exceptional junior engineers

I saw absolutely no compelling evidence to back up his thesis

While I'm deeply sympathetic to the original claim, I agree the evidence is lacking. All I really see is the assertion that AI means onboarding and coming up to speed is faster. Which feels a bit unproven?

(Unrelated but the post has a funny rhetorical thing where it says nobody is hiring juniors then also says if you don't hire then your competition will... But you already said nobody is hiring them?!)