I'm not saying that walking isn't good for you but the truth is that the whole 10,000 steps thing started out as a marketing ploy by a Japanese company selling pedometers.
https://thehill.com/homenews/nexstar_media_wire/4661381-10000-daily-steps-was-a-marketing-ploy-do-you-really-need-to-hit-it/
https://thehill.com/homenews/nexstar_media_wire/4661381-10000-daily-steps-was-a-marketing-ploy-do-you-really-need-to-hit-it/