This is great for people like us living in Asia. But I doubt I will be hiding my email lol. I don't know if it's a thing outside of Asia but LINE (and similar chat apps like WeChat and KakaoPay) are embedded now into our lives, it's not just chat apps for us, it's our payment methods when buying in stores.
LINE is very very popular in Asia like WeChat and Kakaotalk. These are just not chat apps for us, it's our way of making payments when buying at stores, and when you meet new friends, the first we ask is "what's your LINE/Kakaotalk/WeChat ID?" instead of "what's your number". Even for elder people, These are an app they use. Especially with OpenChat, we get to join group chats of people we admire or people.