Relying on heavy weights to produce muscle activity is like cheating on an exam, you pass but you don’t learn anything for real life.
Your muscles should be capable of producing maximal tension with optimal positioning of your bones. Skeletal movement engages muscle automatically.
The way your skeleton aligns when you move determines how effectively your muscles engage to support your movement. Whether you’re exercising or moving through real world conditions.
Cheating on an exam creates dependency on a cheat sheet, much like needing heavy weight to feel a muscle working creates muscles that don’t work well in their natural environment. (Reality, not a gym).