I gave up automobiles about twenty years ago, and attribute my health and slenderness (relative to the rest of my family) mostly due to walking-lifestyle. I spent last month visiting family, and definitely put on weight from thirty days of being sedentary in the suburbs. Awful way to live.
I haven't been able to consistently operate on it for deeper work/code or meetings, but I don't know if I really need to.
Now, obviously this isn't for everyone, but my partner and I adopted a dog and she needs to be walked once or twice a day for about 45 minutes. It's been a great way to get us out of the house every day.
You are absolutely right that adding an hour a day of exercise is a major lifestyle change, but so are a lot of things in life.
I mean if youre willing to walk around with an oxygen mask allday and aren't bothered about possible health consequences, there is also plastic surgery.
You kind of gloss over this, but 8k steps is around 3 miles of walking for the average person. You might be able to get that "naturally" if you live in an urban area and go out on foot every day to get coffee, groceries, etc., but if you're a typical WFH software engineer living in the suburbs, you're probably going to have to spend 45 min to an hour every day walking for exercise to achieve that number. I'm certainly not claiming that this is excessive or impossible or anything, but spending more than an hour a day (when combined with the weight lifting) on exercise and fitness is a MAJOR lifestyle change for most people. I think it's extremely important to be honest about the effort and commitment required. Getting healthy and staying healthy is _hard_, especially if you're starting out seriously overweight or obese.