I think you're forgetting the main reason: the group of people using it to communicate is really small and shrinking every year. The only large group of people who still primarily use SMS to communicate person-to-person is Android users in the USA. Every other country has settled on either Telegram, WeChat, WhatsApp or FB Messenger, or other niche apps. These apps work on both iOS and Android and often also Windows.…
I have most of my friends using some messenger app and based on that I run―because I basically have to run―Whatsapp and Signal myself. But those are all people I know. What would you use but SMS when contacting people you don't? Typically, if I try to reach someone but they don't answer I'll follow up with an SMS to explain what I tried to call for. If it's a co-worker, or an acquaintance, I'll send an SMS to make su…
Here in the UK, whatsapp is the default first try, at least with anyone I've interacted with. The dog groomer even messaged me on whatsapp to tell me dog is ready, completely unprompted.