Realistically why would Peaty be slower as he gets older?
Inability to heal as well as someone 20 years younger means fewer risks taken? Last season or the one before he was quite a way off the pace; hadn't he just had a new kid? That will make a considerable mental difference. I'm the same age as him and I don't take the same risks as when I was half the age with no wife or kids. I don't think he's been quite so bold since that big fall in Windham 3(?) years ago. He was flying that day then had a big wipe out. I don't think he was hurt badly but big falls weigh on your mind. Sam Hill hasn't been quite the same since some big falls and injuries. Old(er) bones don't bend
As for pedalling, as someone said above, there's a lot more pedalling than many people think. That's one area that Peaty is (apparently) rather good at.
Anyone, the great thing is he got in some top 10s this year, so still has more talent and ability than most of the rest of the field could dream of having at the age of 39. Good on him and good on all of them for letting me see some ACE riding and racing.