It won't feel that way though, I understand.
My measurable physical stats are much better than they were at 26. Yes I notice junk food a little sooner and can't handle as much alcohol. But I can run a marathon faster, do better in the boxing ring, and can lift more weight with higher volume.
The main physical drawback that I can see are slower reflexes. That comes out in the boxing ring when going against people 10+ years younger.
> intellectual peak early to mid 20s.
Depends what kind of intellectual peak you measure. My focus is better and more intense. My ability to learn new stuff has greatly increased because I have a bigger vaster framework to hang new knowledge onto.
And I am infinitely better at solving difficult problems in a dumb easy way because I no longer care about showing off how smart I am. This not only makes my solutions easier to build, they're also easier to maintain so future me will have less work to do.
What I'm probably less good at these days is waxing poetically about the sort of very deep thoughts that feel deep to a 25 year old. And pointless brain twisty puzzles that I was never good at anyway.
I'd say these days, intellectually speaking, I'm more of a reliable orc that plows through problems with brute force, than an elf fleeting about using dexterity.
You are. Most people don't realize that until they're in their 40s.