I think walking and strength training are important. I do not believe we have to run on a treadmill an hour a day sweating to death to see benefits.
I actually hate walking for the sake of exercise. But one thing I used to do when I had a membership at the YMCA was the treadmill with the tv screen on it. I don't have cable, so anytime I get to watch the higher channels is a real treat. They have screens on the stair steppers, too, so I can vary my routine. And of course, that's walking and climbing, so I get that benefit. I could go during the day when most people are at work and I'd do four 20-minute intervals. I was in really good shape, and I'd drink at least a liter of water while I walked.
Then I went for a steam and hot tub, swim a few laps, and hose off with cold water before showering and putting makeup on. I considered it a "spa day," so it didn't feel like work. Not everyone has the luxury of taking that much time for self-care in a day, but I've been retired for a long time, initially because of a disability and then I hit retirement age.
It's great, in my opinion, and I started the routine because I'd had the surgery and wanted to firm up and become more active. Mostly, I wanted to start hiking, since I live in Washington state and we have such great trails and hiking areas, as well as awesome campgrounds. It was also an activity I could do with my son, which is another story. Our hikes together led to him getting a job at the Ross Lake Resort for a few summers in a row. When I'd go camping alone and he was at work, he'd canoe to my campsite at night and we'd tell family stories around the campfire, which was such a tender time for me. I'm so grateful for it.
I guess what I'm saying is that one thing can lead to another. I hate deliberate walking for exercise, as I said, but I didn't mind the treadmill to build my muscles and stamina, which led to lovely family time.
Oh, and I've told this story before, but I once hiked up about 6000 feet, which took me all day and it was dark when I rolled out my sleeping bag. I was too tired to pitch my tent, so I just drank a tiny bottle of wine and crunched up dry top ramen, which is a great treat, really salty, a recipe I learned from my son. I was laying on my side and I had salty top ramen crystals under my fingernails. I was almost asleep when I felt something nibbling at my fingertips, then felt teeth and soft biting. I was sure it was a bear because i had just seen a mama bear and cub running past, silhouetted in the sunset. As the toothy feeling got bigger, I decided I had to fight back, so I suddenly rolled over and screamed to scare the animal. As it turned out, it was a six-point buck, and I scared the shit out of him and watched him jump up and bounce away in the shadows.
I never would have had that experience if I hadn't committed many months to the treadmill, so I could get strong enough to hike that high. So, sometimes a treadmill can be a good thing!