Also in my 60's.
I don't enjoy riding much over 90F and/or high humidity. If I plan well, I'll get out early on roads that are still in morning shade, otherwise I have a kayak...or a basement trainer.
I rode most of this past Winter though, including a few segments down into the upper 20's F. Slipping a heat pack into my Winter mitts is more comfortable than overheating in Summer. The only downsides of Winter are snow/ice/salt/sand, and short battery life on the crash-cams.