We’ve been on prepaid for many years. I bought myself out of my old Verizon plan to go to Virgin Mobile because usage overages (at that time not unlimited but now are) didn’t result in huge fees like they did with VZ. Then I switched to Google Fi for a year or two, then to Metro PCS where we are now.
Currently have unlimited everything (including data), 2 lines for $80, 3 for $90, 4 for $100. Free nice phones too, unusual for prepaid. T-Mobile network so great coverage and the data speeds are comparable to or faster than my home wifi.
I think the competition from prepaid plans has forced the postpaid to stop doing contracts and lower their prices to compete. And still , they’re losing market share.