As always, this could be any number of things. The only context we have is what's given by people who are known to hype and manipulate the situation (the bokeh triangle, for example). We're led to believe this is a trans-medium craft and that the Navy has no idea what it is. But, of course, the reality of the video is that this is just something floating into the ocean and we have no way to know what the Navy thinks about it.
It could be inter dimensional beings but we can also imagine many other things it could be. Unfortunately, with the information flow controlled it's virtually unfalsifiable for those who choose to believe it's something extraordinary. But that burden of proof is still on them whether they care or not.
The fact that this comes from the UAPTF doesn't mean much without a statement from them. My guess is that cases not positively identified, or cases with just limited data, may be sent to them for investigation whether or not they have a "good" idea of what it is. From there, the ambiguous ones can be cherry-picked to tease the public.
The dialogue in the video is compelling depending on your bias. But it's always the case that you don't know what something is until you do. For all we know there is other evidence that points to it being a balloon or drone - but that evidence is omitted by the leaker or Corbell (for obvious reasons), or by somebody else (for unknown reasons). Again, it's very possible this is known to be a balloon or a drone but it finds its way to UAPTF and remains "unidentified" until they can verify specifics - purpose, origin, etc.
It could be something neat! But there's nothing new here. If it weren't for the "trans-medium" narrative that's been pushed by a select few UFO characters this probably wouldn't even be as exciting as it is. For all we know, judging from the dubious history of UFO industry, they could have been pushing this particular hype in anticipation of releasing this specific video. Entire branches of UFO lore have in the past been created from sporadic single-point evidence and are still going strong today.
We can only guess at their motives. But if anybody knows how to psychologically build a narrative in this way, it's a film producer and a counterintelligence agent.
