One interesting factor to consider in the question of cell phone popularity is the nature of the available infrastructure in the country.
Consider Brazil, not necessarily third world, but it is the country I will use for my example.
In the 1970s, my wife’s family were on a waiting list for many years before they were allowed to have a phone line. Even by the early 90s, it was possible for the owner of a telephone line to rent the line out for a substantial sum every month. And the line had intrinsic value.
Sort of like the taxi medallions in New York, but not nearly as pricy.
The problem was that Rio de Janeiro just didn’t have the telephone infrastructure to allow every family to have a phone line. Demand far outstripped supply.
Then along came cell phones. People who had never had home telephones were able to pay higher cell phone fees, but get their own phone almost immediately. The infrastructure was much easier to install, and sort of leapfrogged the existing land lines.
By the end of the 90s, the phone line that my in-laws owned that had been worth thousands was worthless because now cell phones had taken away the demand.
I imagine that strange distorting factors like this, unfamiliar to most first-world residents, might be a factor in the assertion of the OP.