There is nearly no way for a PI (head scientist) to cite everything that they say. Knowledge at the forefront is cobbled together from little whispers, tastes of failed experiments, hearings-ons from colleagues, intuition, guesses and literally decades of thinking. And so when speaking abstractly (as these videos are), they are often less wrong than anyone else (Clapper, this is how you use that term...). If you were to press them on specifics, they would become mostly correct and dig up where they got that nugget of wisdom, though simultaneously losing much of the power of generalization. In that sense - the generalities are always slightly suspect, but of far greater quality than anyone else's generalities. And usually the generalities you'd like to hear about from the cutting edge are those that there is no consensus about anyway.
So in that respect, I'd say the generalizations of cutting edge scientists are usually the least wrong, rarely perfect, always insightful, and nearly impossible to source. They are the tenuous 'hypothesis' writ large to which their career is attesting. Citation of such is nearly a moot point, as no generalizable experiments yet exist.
On the other hand it'd be a great resource if they listed to the side a paper or review about some of the stuff they just spoke of. It'd be trivial for them to name a paper or two that they find dominating their perspectives here.
Great idea! We'll put it unto the to-do list.