How is FaceTime/iPhone different than other technologies that came before it and offered video calls? I feel like I’m missing something when reading posts such

How is FaceTime/iPhone different than other technologies that came before it and offered video calls? I feel like I’m missing something when reading posts such as this. Especially around the ongoing discussion around blue/green sms/messages. I don’t know if it’s a US thing, age thing, or something else, but at least for me mainly interacting with people in Uk and greece, and with a predominantly iPhone-using group of friends and acquaintances, I’ve never used either FaceTime or iMessage. People will use a mix of Facebook messenger, Whatsapp, telegram, or signal to text or voice/video call but that’s about it.