Europe here too. SMS is still my main way of writing short messages to people. I refuse to use Facebook Messenger or WhatsApp and that's what most people use. I could not even use WhatsApp, my phone is not supported.

Thankfully Signal is taking off in my friend circles, but SMS is what will work best on my phone and what will wake it up. Signal works well when I'm on my computer.

SMS is also what I'm 100% sure will work when contacting someone through their mobile phone number.

SMS sucks, but it's ubiquitous. The rest of the messaging market is heavily fragmented.