I guess Verizon's in more of a rush than most to kill 3G as theirs is based on a quite proprietary Qualcomm CDMA-2000 technology [...] 2G GSM and 3G UMTS can be typically supported on more flexible modern RAN infrastructure
That doesn't seem to be the case. AT&T dropped their 2G network in 2017, and announced 3G will be shuttered at the end of this year (2021), necessitating VoLTE. T-Mobile has allowed its 2G network to linger on, while 3G will be killed off this month.
Biting the hand that feeds IT
