At the higher speeds of dial-up modem, things did eventually get standardized, and we got 14.4 kbps, 28.8 kbps, 33.6 kbps, and finally 56 kbps, which requires one end of the call to have a digital phone line (ISDN), not analog.
I digress. We ended up going through the same evolution of slower to faster speeds with 2G phones, 2.5G, 3G, 3.5G, 4G LTE, 5G. Things didn't get really interesting until 4G LTE, with high speed and low latency approaching the slower tiers of home broadband.