Actually, for about the last 5 years (I'm 67...) I've been cancelling trips in weather where the overnight temperature is predicted to be below 25. I just don't enjoy it the way I used to - particularly the sitting around in a chilly camp before bed.
Perversely, I find that spring, summer, and fall hiking in an all-day rain, and making camp in the rain doesn't bother me the way it used to.
Long ago I decided that hiking/camping/backpacking/outdoor activities is not or should not be an exercise in what you can tolerate. I do outdoor activities to enjoy myself, not to congratulate myself on what horrendous conditions I can survive.
If really bad weather is predicted, I do not go. Period. Occasional showers are OK, gale force winds are not. Soaking rain for days is not. Major storms are not. Chilly at night is OK, record cold and freezing rain is not. I do not start out if anything more than a shower is taking place.
I enjoy myself more when I do not have to huddle in a sleeping bag after having a hot drink to maintain body temperatures. I like to socialize (obviously when I have a companion) rather than wrap myself in every piece of clothing I own and close my bag. Evening trips to the bush are less unpleasant when you are not shivering.
This is just my choice, it does not have to be yours.