Although it may have the same fate, AIM suffers from being computer only when it was in its prime. (maybe always) Anywhere I go I can socialize on whatsapp, or snapchat or whatever app.
I don't think it was purely Facebook that killed MySpace and AIM, it's that they didn't get on phones quickly enough.
However unlike SMS it didn't cost eye-watering amounts of money to use. Whatsapp never became popular in the USA because most people on pay-monthly contracts received large SMS allowances.
In the rest of the world, networks felt threatened by SMS -- if texts were too cheap then people would stop making phone calls! So it was universally crippled with ridiculous limits and fees. Even in 2018 it costs me a lot of money to send an SMS, and I don't know anybody under the age of 35 who uses it.