Well, that is surely by far the main reason anyone uses any messaging app. The majority of people don't care about features or even privacy, and use the app tha

Well, that is surely by far the main reason anyone uses any messaging app. The majority of people don't care about features or even privacy, and use the app that everyone else is on. In Europe/the UK at least, that seems to be WhatsApp. Outside of techie people, if you ask someone to use something like Signal you'll be met with "why? I already have WhatsApp". "larger user base" is an understatement; the difference is several orders of magnitude. (on a personal level, I don't enjoy using WA, but it's necessary here unless you only communicate within a bubble of tech workers)