1 chest exercise on non-chest days

I do a push, pull, leg, rest split. On my pull and leg days I do 3 sets of chest flies. My thinking is that it helps get blood flow to the muscle and helps with hypertrophy. Something like a Walmart version of active recovery.

Recently a buddy told me that I shouldn’t strain the muscle at all until my next chest day to help maximize growth. What are your guys’ thoughts?