I think Verizon went full corporate mode and stopped investing in their network to maximize profit. When I was in T-Mobile store there were at least 6 customers there that all asked to switch their number from Verizon to t mobile. T mobile is still investing in their network which is why It is still getting better.

Apparently they just upgraded a tower near me because I can now get okay 5G outside my house. Inside is still super iffy but I'm on wifi by that point.