I don't find it strange at all. TFP's announcements for this game are almost solely on social media as well. Most postings here about new stuff comes from forum users who copy/paste or link info from TFP's social media posts. So why would you expect them to post info about another game here? This forum isn't a general TFP forum, but a forum specific to this one game. I mean, the new game is in this "universe" and so could be posted here, but this forum was set up for this game specifically. I'd expect a different forum or at least subforum (like the console section) for any other games that may be in this "universe." And even then, the forum isn't their main way to advertise new stuff, so it will probably happen, but I wouldn't expect it to happen soon. More likely, any forum related to that game will be on Illogika's site and not on TFP's. But we'll see.
As far as the game.... I certainly will not be buying it or playing it. I've got hundreds of games that I've bought and even so, that one will never be in my library unless it's given to me free for some reason or part of some collection I want to buy. A 1v4 game just sounds really bad to me. I get some people like that sort of thing, but it doesn't interest me in the slightest. I don't plan on even looking into any information about the game. The 1v4 was enough to make me not interested in it or any news about it. And I wouldn't be surprised if the majority of 7D2D players will feel the same, so their audience is very different and posting info here probably won't be much value to them.