No, I started pumping at 6wks because wanted to establish breastfeeding & my supply. The pumps then were not as good as they are now as they could maintain supply but not increase it like breastfeeding direct to an infant would.
I then pumped and built up a freezer stash for 4 wks before returning to work FT (no phased return). I did this by pumping from one breast while feeding from the other and doing a pumping session after the midnight(ish) feed.
There’s not much difference between expressed breastmilk and breastmilk from the source, not enough to the baby at any rate to say we can’t get equal economic power because we are side stepping biology by using a breast pump or formula (mixed or sole formula feeding). Besides my DC always got breastmilk from my boobs several times a day, every day except when I had to travel away for work. There’s no impact by not having every feed each day be direct from the breast.