Why does nobody talk about how much better a simple email list is than social media for real growth?

I mean, I ran both for my small bakery for a year. We posted every day on Instagram and built a list of 500 people who signed up for our newsletter. The social stuff got likes, but when we sent a Friday email about our new sourdough, we sold out in 3 hours. The email list just brings people back who actually want to buy. Has anyone else found social media doesn't really drive sales like they say?