[evilbob93]

... and?

I agree that years aren't necessarily a good metric for experience, although I have decades in IT - started when I was 19 and retirement is a real thing I have to consider.

Years do give you some experience that isn't translatable to the resume: after a while, you've seen through most of the tricks that management likes to try but which the younger colleagues haven't learned. Having older folks around can spoil the surprise.

My personal theory of the roots of ageism has this as a pillar.

[peteradio]

What kind of management tricks might someone be missing who hasn't been around too long?

[jseban]

They try to make you commit to additional unofficial work/projects for which you get no extra time or resources. If you fail and burn out, that's just you being a bit "overambitious", and if you succeed, they will just make if official. In that way, they can avoid owning up to any failures and only take responsibility for the successful ones. So you have to be a bit careful in casual conversations with the boss about ideas and possible improvements.