So the conclusion was benefits start to plateau around: for women ~7500 and men ~8000 steps. Truly 10k not a bad estimate. So the answer is yes roughly, get out and be active.
I also think that 10k can serve as a psychological goal.
Anyhow recently I heard a someone say: Don’t become a slave to the metric, the glass is half full. If you did 7k steps, that’s still better than 3k. It’s not about fulfilling the 10k, more about searching for opportunities where you can get your steps „for free“. Ordering food? Maybe get it as take away. Using the elevator to go to the 11th floor? Walk up the first two or three.
The steps are a proxy metric for activity, you can correlate it with how you feel or with the amount of backpain you experience in the evening. I don't see how I'm loosing looking at this metric.
Even for me, as much as I hate giving away my medical data, I love compiling GPX files of hikes I've been on, or keeping streaks of commuting by bike everyday.
Metrics are great, and I don't think it's as simple as a dichotomy between being all about number crunching, vs all about feeling the grass under your feet. One can do both.
Someone reading "10k steps is not scientifically grounded" might think "well then screw walking, I'll just watch TV", whereas the actual truth is "It's not 10k, more like 9k". Sure, 10k might not be scientifically grounded, but it's close enough and has a big enough benefit that it's not worth refining the estimate.
2018: 9411
2019: 9250
2020: 9933
2021: 9277
In my case, pandemic changed absolutely nothing in my lifestyle. I live in major North American city FYI.