Comparing this situation with Twitter is erroneous. It's not the same thing at all.
Twitter is a single thread with no topic distinction that runs unendingly (and provided by a third-party platform that can force their will on users if they want to.)
Flarum (an open source system that should be customizable) is made up of many individual conversations, most of which end within a few posts for most project uses. They will never keep going unendingly over time. They will just terminate and sink out of site.
So then what do users see when then've come to the end of a 5-post discussion? Nothing? Seems like a good opportunity to show some useful links, copyright statement, contact info, partner logos, etc or whatever. Or does it jump to the next topic in the Tag? That would be bad usability, IMO, confusing users who are trying to get some task done and don't want to spend all day swimming through a fish ladder.
As an example of wanting the discussion features but also wanting a footer: We use a footer to provide partner logos for collaboration commitments we have with other providers, and we'd expect to do that in Flarum too if it's going to be a site in our collective web real estate. We want to have consistency across our holdings. We don't expect to have unending conversations. We could benefit from having a footer as continued exposer value to our partners.
I don't see why this couldn't be a feature in Basic admin settings that you allow a given site owner to turn on or off. If on, no footer. If off, footer. Shouldn't be hard. An open source system should not be forcing the inability to add content or not, and a footer is an important website content block for many sites.
2 cents
