You might be right, if it is a derivative work and not a new one. There’s some evidence that the authors consider it a new one because they’re attempting to change its license.
The BSD license doesn’t explicitly convey the right to create derivative works but it does convey the right to “modify” the software. (They seem similar but “modify” is a narrower verb.) So is this a modification? A derivative work? A new work entirely? If it shares no code with the work from which it was derived, things are more complex than it may seem (and it no longer fits the “compressed video” analogy very well).
The law and courts are not really settled here from what I can tell. I expect some day hundreds of millions $$$ will be spent on this