WHO recommends at least an hour of moderate+ activity per day which virtually nobody with an office job in the 1st world manages to do. The notion that you could accidentally do too much exercise is ridiculous unless you go all-in-gym-bro.
An hour or more of moderate activity per day? Dunno about that impossibility of one hour. Perhaps you're talking about some hectic Amazon-style working environmen,t or people that just had babies, or commute for 1 hours each way?
"Adults aged 18–64 years"
> Should do at least 150 minutes of moderate-intensity physical activity throughout the week, or do at least 75 minutes of vigorous-intensity physical activity, or an equivalent combination of both.
> For additional health benefits, adults should increase their moderate-intensity physical activity to 300 minutes per week, or equivalent.
> Muscle-strengthening activities should be done involving major muscle groups on 2 or more days a week.