I'm 45.

Been road cycling for 30 years. Was competitive when I raced under 18s to my mid 20s. Now I race the very occasional crit and a maybe few TTs a year.

I coach and mentor younger riders.

My passion hasn't faded at all.

The "steady state of decline" you describe is not something that I recognise. I may be slower but I'm certainly as "fulfilled" by cycling as I ever was, maybe even more so.

Guess it depends what you're looking for.