I really think Discord should have a 'seen/read message' feature, mainly for DMs. I can never tell if someone has read my message or not. It'd be really useful to know if someone's ignoring me. Overall, I feel that it would be good to know if someone read a message I sent without having to reply or reacting to it. I'm unable to tell if a friend of mine read my message without having to ask if they did. It might be just me, but it kind of irritates me a bit when I do have to confirm. Also, for those saying that you can just react to a message, not everyone reacts to a message showing that they read what you sent, hardly anyone that I message does.
I don't think this would work for servers, but it would definitely work for direct messages. If people have mixed feelings about this, maybe this could be a feature that can be toggled off/on. A lot of other messaging apps have this feature, but I also think Discord should also have this. Overall, I think this would be useful for me and other people.
(Edit): This has so many comments, thanks, guys! But we really need more upvotes in order for Discord to see this. I'd really love for this feature to be released, please upvote guys. Really appreciate the comments from both sides. Hopefully, they'll notice eventually.