We've been using the name for 26 years which is legal ground by itself. 0ad and WFG are under the patronage of SPI the non profit behind debian and arch linux. Should we have legal issues they are the ones we would sollicit

No, https://tmsearch.uspto.gov/search/search-information , 0.A.D, 0ad, wildfiregames, wildfire (software category), etc, are not registred as brand trademark. Perhaps it's important to formalize this development group and the project itself before someone takes advantage of it by registering the trademark in their name, preventing future distributions of 0ad. There are well-known cases like OpenOffice, where Oracle, after acquiring Sun Microsystems, registered the name and it ceased to be free software. The community had to create a new fork and change its name. Something similar almost happened with Mozilla Firefox. Debian wanted to create its own attended version of Firefox (Iceweasel), but Mozilla made a legal claim for the use of the name and trademark, which were legally registered despite being free software. If you want a personal recommendation, I suggest you create a non-profit foundation dedicated to maintaining 0ad to keep the project free and perhaps eventually generate indirect benefits by supporting the developers. As a foundation, you'll be protected from legal action for patent infringement. They registered the foundation as wildfiregames and under that foundation they registered the name 0ad. A very clear example is the case of doom 1 and 3, idsoftware released the source code and the community began to create incredible mods and forks. What was not distributed and was copyrighted were the models and designs of doom, the brand and so on, but the engine was free and people could create new games without the need to use the same models. But idsoftware was a legally registered entity with the doom trademark registered in its name, regardless of whether the code was free or not; this gives them much more control. I think you should do something similar, but under a foundation scheme.

I think the biggest thing is they were impersonating 0 A.D.'s brand which I think is protected.

The video is no more available on YouTube. Are there copies elsewhere?

You two should get a room, lol.