I'd contrast that to the experience of AT&T postpaid which is radically better.
The truth about MVNOs is that you are riding on the back of the bus. As long as I was using cheap Android phones on MVNO I was always wondering "why do people get so excited about apps?" and "why is infrastructure in the US so bad?" but when I got a postpaid iPhone it was like... yeah, this really is a world-changing technology.
https://silent.link is a good option for cheap data. Accepts cryptocurrency and data doesn't expire. This might be the cheapest for people with variable data usage or low amounts needed.
https://jmp.chat is a cheap option for numbers.
Click the dropdown labeled "Broadband Facts/Consumer Disclosure" and you should see this:
This Price is an introductory rate.
Tenure Period 12 Month
Regular Price $252
Current offer Price $75