It's really annoying that on some websites you have to open up multiple dropdowns to reach the login page, also passing five sign up buttons on the way there. It's even filled with dark patterns, with the sign up button blinking and screaming at you to click it every single time, while the login button is made smaller and grayed out. I remember GitHub pulling this shit some time ago. Once I truly couldn't find the login button and gave up, opting to guess the URL/find it in history.
What is even the purpose of that? Is it truly a scheme to get users to sign up multiple times for the same service so that the user number goes higher? That seems too dumb.
The parent poster then did not realize they had created a new account and, even when it told them their email address was registered to a different account, somehow didn't realize they should go click login instead.
I think the easiest way for discord to make this a not-confusing experience for people who aren't tech savvy enough to click "login" to login, is to make it so the signup flow is a normal explicit "Enter email, enter display name, enter username" prompt, not a flow where they silently create a username if you _just_ enter a displayname.
The reason this would help is because forcing the user to enter a username early on lets you display a "Would you like to login instead?" message if the username conflicts.
Having the user enter a non-unique displayname, and silently creating a random unique username, means the signup flow no longer has the ability to say "Are you sure you don't want to login?"
Of course, discord mostly targets relatively tech-savvy users, not the average hacker-news-user, so it probably isn't that big a deal for their main demographic.
But if you do this you better do it everywhere you use email. Otherwise you can get some pretty nasty bugs where two emails aren't considered the same sometimes, are are considered the same other times.