Isnt having a cellphone mainstream
Perhaps, but good luck finding a payphone anymore.
Cell phones killed the payphone. Tracfone or nothing.
Do a Google image search for Masai Warrior with Mobile Phone and then we can talk about how cell phones are mainstream.
Might as well say using a hammer and nails to build a cabinet is mainstream.
P.S. It also works for Zulu warriors, Buddhist Ascetics, Jain Monks, etc