You were overtraining and covid forced you to rest for once. No 40 year old should be doing 100 pushups per day 7 days a week. That's ridiculous.
The last 6 months, minus a week has been with 25 of them in burpee form.
I break them up throughout the day, it's not a lot of exercise at all. It feels like the bare minimum to stay in overall functional fitness shape. It's nice to have the strength to do whatever I'd like to do on tap anytime.
9 ultramarathons in a year may have been over-training however. (Towards the end it was getting to be one every other weekend just for kicks.)
Overtraining is a real thing, and this person is doing it. Either that or they're embellishing to make a point.