I've lost 2+ inches on my arms, chest and legs after 20 years of working out fairly consistently. I was the strongest I had ever been just before COVID-19 hit. I'm not super-depressed about it quite yet, because the gym had become a bit of a crutch for avoiding dealing with problems in my life.
But after so many months off, I'm reaching the point where the lost gains might not be recoverable. I have to decide sometime soon whether to get back into the gym or give it up permanently.
It's not a total loss since I've been doing handyman work for my boss and 50 incline pushups 2-3 times per week. I'm in generally good health and my face is thinner. Still stinks though.
I bought a used weight bench and plan to use it soon. And I'm still paying my gym membership, only $20/mo for life at a converted Gold's Gym. But we get such a boost in the first 6 weeks of n00b gains after a break that I feel it's better to go all-in rather than dabble.
Oh and to answer your question: pumping iron is a hack. My girlfriend does kickboxing, and it's a tremendously physical exercise revolving around burpies and other crossfit-style functional training. It's really good. But, I feel that weightlifting provides a much higher bang for the buck because it takes advantage of 2 to 5 day overcompensation cycles in the body so that gains continue indefinitely. So my intensity under the bar over an hour and a half period never even reaches the intensity of her warmup. Yet I put on perhaps 2 to 4 times as much muscle as I would cross training, for 1/2 to 1/4 the effort, which works out to about a 4 to 16 times better return on investment (an order of magnitude better result).
I pump iron because I'm lazy, is what I'm saying.