Agreed. I started working in tech when I was 22--now I'm over 30. I've never witnessed old-age discrimination. What I have witnessed are start-ups, built on newer tech, (AWS over on-prem, nosql over relational, etc), passing on candidates whose last reference book was the Data Warehouse Toolkit and still want to be called WebMasters.
The law of the tech industry is when you stop learning--at any age, you lose market value.
You can always catch-up and learn something that becomes important/mainstream, but you can't un-waste your time deep diving on a dead-end technology.