Intense exercise that doesn't promote muscle growth isn't ideal. Having muscles into your 40s,50s,60s etc is how you stay mobile and fit far into your late life. It's also how you prevent the majority of naturally occurring pain from joints, back pain, knee pain.

There's enough science for people who want more than the minimum. Listen to Andrew Huberman, David Sinclair or Peter Attia if you want the latest in general health. Cardio is very important but you want both and I would recommend starting with muscle promoting exercises first then everything else. That is the fountain of youth along with sleep, diet (mediterranean) and close bonds with family/friends, sense of purpose and belonging.

But like walking, people shouldn't be aiming for the literal bare minimum of effort. Build muscle while getting lean as you age is your goal.