But you can easily test this yourself: Go and try to create a new Discord account without a phone number. Then try to use it.
I couldn’t, Discord immediately forces me to add a phone number on login.
Maybe it’s regional? Or they have different behavior based on your email address provider?
I gave up on having a second account.
I personally like to keep it on. Most of my messaging is with family and friends and it’s good to know if someone read or hasn’t read my message.
Especially if things are time critical. Picking someone up? Asking if they need anything from the supermarket? If I see that they read the message I know that they are going to reply in a moment. If they didn’t even read the message I won’t have to wait around / can guess that they are currently in the car or wherever.
Sometimes you also have a spotty connection, so the received + read receipt can tell you if they actually got your message.
In general if someone sends me a message and I read it… I’m going to fucking reply to it (if I’m not super busy, and even then I might send a quick message back). I seriously don’t get people who just leave things on read and then forget about it.