I'm confused as to what exactly is wanted here, question 3. Does Area 51 want me to build a website? A change.org petition? A subreddit or a discord? What do I need to do here, are there pre requisites for this community?
There's actually a pretty broad range of communities you can link to. The platform on which you gather support doesn't really matter. All you need is an active community large enough to launch a site. At least 100-200 users is usually enough.
All of the examples you mention would work just fine, as long as you have enough active supporters. A change.org petition, subreddit, or discord would all work just fine. I've even known users who started a chat room on chat.stackexchange.com and gathered enough support there, and... it worked pretty well.