Since you mention education, let me school you on the fact that Valve does in fact own the trademark for ‘Portal’
You say ‘there is no reason for such assumption’ even though the assumption is built right into title of ‘Portal’. The person reading it is already ‘assuming’ this is in reference to the Portal series made by Valve. If ‘there is no reason for such assumption’ then why else would anyone assume it has anything to do with the Portal games? Hell, why would anyone assume it’s a video game at all?
It’s obvious that the trailer is about the Portal series and if you are unaware of anything about the fan mod there is no way for anyone to be able to guess that the video is not about an official new addition to the Portal series. Particularly considering Valve just released an update to Half-Life 1.
How pathetic that you can’t just have a reasonable discussion and instead resort to flinging insults like a monkey flinging their own shit. Grow up, kiddo.
Trademark is not ownership of the word. Anyone and everyone can use the word “Portal” to speak about the game, its mods, its lore, fan content, likes and subscribes, etc.
The video was originally titled in the already common pattern across all industries in the media: “Work title: Work subtitle - Official Announcement”. It’s honestly not hard to parse, and it does not constitute in itself any judgment on whether it’s Valve’s Portal or the Portal of anyone else who can and is allowed to use the name (think eg.: I write my college thesis and announce it as “Portal: Why the Game is Good - Official Announcement”).
I do be fair and mention I come from the Pokémon fandom, where (until the series went into Yearly Crunch) the amount of fan content more than 7x-ed the amount of “official media” so one learns to parse announcements and titles faster. I guess I’m trained by a different internet than yours. However I don’t get why you think I’m somehow “flinging insults”, but I guess that just strengthens my point that elementary education should be revisited.