I haven’t watched many of Juan’s videos, but the ones I have seen, I liked. In this particular video, Juan discusses what we do know at this point (not much), and spends some time on analysis of the ADS-B flight profile, which indicates a nearly vertical descent into the water. There are only a few things that would cause such a descent, but one of the most prominent is inflight breakup of the aircraft. Juan then goes on to discuss a prior structural failure in an Otter. During the last couple of minutes of his video, Juan says (several times) that the cause of this crash is unknown.
I feel that speculation of the cause of a crash can be beneficial, since it usually results in a heightened awareness that things can, and do, go wrong and that none of us is immune to the consequences of our actions. This is particularly valuable since, as noted above, it can take months (or longer) before an accident report is released. Most pilots will speculate on the cause of a crash … and this could be a good thing.