To be competitive in the sport, you need the pyramid method with the high volume base of light effort, middle of volume of sold effort (e.g. lactate threshold work) and a peak of intensity (e.g. interval training).

This is about health.

High volume of exercise is damaging via oxidative stress and other ways. Weekly training volume is the most reliable predictor for injuries.

If health and basic fitness is the goal, rather than bringing home the gold, you can add intensity to just a fairly small volume of moderate exercise, or perhaps even none at all, other than a warmup and cooldown.