What's making me feel old isn't so much what's happened to me or my physical limitations. It's what's happened to my contemporaries.

My surfing bud had a minor stroke, and will be out 6 months from rotator cuff surgery.
A friend (new to cycling as of a couple of years ago) had a spinal stroke and is now a complete quad(!)
Another friend is now walking with a cane.
Another has given up skiing because he's too "old."
Another few dealing with afib.
Partner has been off the bike for 4 months due to back pain that won't go away.

The list goes on. So as time goes on, I feel older and luckier at the same time. Whether I'm slower or faster than I used to be is in the noise compared to other stuff. I'm grateful for what I am able to do.