At the beginning of this year, 2G and 3G subscribers accounted for 46 percent of the world's mobile subscribers, but contributed only 27 percent of total global mobile revenue, according to a Strategy Analytics report.
By 2023, that revenue share will fall to 10 percent, Strategy Analytics says.
Africa can be considered a special case, where countries have ARPU below $2, so there is limited room to maneuver through subsidies to promote subscriber migration, the report said.
However, Africa and other developing regions have made good progress in promoting 4G services.
For example, Airtel's 4G network expansion and "Big Packages" in Africa have driven subscriber migration to 4G, resulting in significant increases in both average data usage and data ARPU.
Airtel has generated 3/4 of its revenue growth from data over the past year, with 4G accounting for 29% of data subscribers in March 2020, up from 18% last year, and 4G revenue accounting for over 60% of Airtel's data revenue.
According to Strategy Analytics, 2G rollbacks also typically require a long lead time, especially when it comes to the migration of 2G IOT services.
In this case, operators may focus on shutting down 2G handset services and retaining only a thin 2G network to serve 2G residual IOT customers.
In Africa, attention also needs to be paid to the importance of the 2G USSD function for mobile money services, which is an important source of revenue for some operators.