With respect, you haven't seen ageism until you hit 40 or 50. When you've been told that you have a great rèsumè and that they're looking for someone just exactly like you but five years younger and would you be able to give them any suggestions, then you've seen ageism.

I've never been a manager, and I wouldn't want to be. Technical Team Lead is as far as I would want to go, and I haven't done that yet.

As you get older, it becomes easier to become a contractor or consultant, as opposed to working in-house. Then they expect you to be a bit older, because you've got more experience.