Covid: it is hard to discuss this at times, because there is such a great variance in experiences.
Here is my experience with my age peers.
2 of my good friends got it, but only found out they had it via a test. It wasn’t even a cold for them.
2 of my other friends got it and ended up hospitalized; one of them had their oxygen levels drop into the 80’s. He was hospitalized for a month and almost died. He has recovered since. Mind you, he was an accomplished ultramarathon runner.
The other also was hospitalized and, 3 years later, has not recovered. She went from being an ultra marathon runner to barely being able to walk.
I knew of someone else who ended up wheelchair bound and lost a limb!
Me: sick for 2 weeks (worse than any flu I had) and it took me another month to get up to speed, physically. But I did recover at home.
My point: people’s experiences are all over the map, so it is hard to generalize.
Age: So, are you really “too old for that?”
It depends. Most of us have chronic conditions of some sort. My right knee now precludes my trying to run; the last time I tried I could feel the pounding on the top of my shin bone. My back precludes squatting and going for max deadlifts, and it makes open water swimming all but impossible (the “sighting” motion where one lifts their head to look puts the back into extension).
But others do not have this set of difficulties, and still others have the body awareness to know how NOT to put their respective condition into a painful position.
So, the answer to the question is “it depends.”
I do know that my days of jogging to the pool, swimming, lifting, jogging home and then going to work are pretty much over. I have to be selective and I have an “energy” and a “back” budget.
Life of an old goat 