One interesting bit about American age discrimination law is that it only works one way. It protects those older than 40, but you can legally discriminate against young people.

If ageism in tech is real, then older programmers are being systemically undervalued by the market (probably in a huge way since I’d expect older good programmers to be be better than younger good programmers).

If I was doing a start up I might advertise roles that are for 40+ year old candidates only and see who I could attract.