I think they are reacting to competition. MidJourney is amazing, was easier to get into, gives you commercial rights, and frankly I found more fun to use and even better output in most instances.
It’s clearly personally preference, but I loathe Discord but love it for MidJourney. As you said, there’s an interactive element where I see other people doing cool things and adapting part of their prompts and vice versa. It really is fun. And when you do it in a PM, you have all your efforts saved. DALL-E is pretty clunky in that you have to manually save an image or lose it once your history rolls off.
I have access to both and they're good for different things. DALL-E seems somewhat more likely to know what you mean. Midjourney seems better for making interesting fantasy and science fiction environments.
For comparison, I tried generating images of accordions. Midjourney doesn't really understand that an accordion has a bellows [1]. DALL-E manages to get the right shape much of the time, if you don't look too closely: [2], [3]. Neither of them knows the difference between piano and button accordions.
Neither of them can draw a piano keyboard accurately, but DALL-E is closer if you don't look too hard. (The black notes aren't in alternating groups of two and three.)
Neither of them understands text; text on a sign will be garbled. Google's Parti project can do this [4], but it's not available to the public.
I expect DALL-E will have many people sign up for occasional usage, because if you don't use it for a few months, the free credits will build up. But Midjourney's pricing seems better if you use it every day?
[1] https://www.reddit.com/r/Accordion/comments/uuwrbj/midjourne...
[2] https://www.reddit.com/r/Accordion/comments/vz9zxw/dalle_sor...
[3] https://www.reddit.com/r/Accordion/comments/w0677q/accordion...
Edit: Joined the discord via the beta and got in. Thanks a lot for the heads up!