TBH I consider that a feature, to guard against spam and trolls.
My ideal project forum is one where anyone on the internet can read the forum, but contributing to the forum requires some bare minimum effort of creating and verifying a new account. Both of those are the opposite of what Discord does.
I frankly don't mourn the loss of users "who can't be bothered with yet another account". Putting thought and effort into forum interactions takes longer than creating an account, so someone incapable of the latter is usually incapable of the former.
Have you ever managed one? I have, and it's a regular occurrence. Though not necessarily something that ends up being visible to every user (unless you happen to be around precisely when it happens, before we delete the content).
IMO Discord is a non-starter for many tech people due to privacy issues and frequent/random phone number requirements. I and many others are completely unable to use it even if we wanted to, because immediately after logging in you get hit with a phone wall. Not everyone gets this but it indeed happens to a wide enough array of people to be quite problematic IMO.
My ideal project forum is one where anyone on the internet can read the forum, but contributing to the forum requires some bare minimum effort of creating and verifying a new account. Both of those are the opposite of what Discord does.