Read the title and thought "Oh, hey, someone is making a spiritual successor to Battlefront 2 that is just removed enough from the IP that Disney might not C&D and Valve might even offer legal help in case the D tries to kill the project and studio by drawn out litigation." Then, I saw the beginning of the trailer and started to have doubts of this seeing the light of day. Finally, I saw the end and said, "shit, they're using the damn Star Wars music, too. Now Youtube's content ID system is going to summon all of Disney's lawyers to come suck their blood dry. The game is now on an express lane to doom (and not the good kind with chainsaws and BFGs)."
My best guess is Valve okayed this so the controversy from Disney's Army of Atrocious Attorneys(TM) doing their thing will drum up free publicity and support for when Valve hires guys from this studio to make their own version of Battlefront. I don't know what's worse Disney and EA regurgitating a piss poor Battlefront sequel while condemning fan attempts at reviving what made the old games great or the possibility of Valve tricking this team into thinking Valve has their backs, waiting for the megacorp to strike and "offering" to take them in. Maybe I'm just pessimistic and paranoid here, but one of the companies know for hiring mod teams to make their new games suddenly supporting something known to rile up IP lawyers is setting off some warnings in my head.