I would honestly disregard Sub Brief almost entirely as a reliable source of information, he's guilty of a lot of Wikipedia/SeaForces regurgitation and has some pretty questionable political leanings which spill heavily into his work at times. To say they are a serial bullshitter who sometimes just makes things up is not off-base. He leans on his career to lend himself credibility, but has been caught multiple times getting things wrong that are public source directly related to his former profession. Countless black marks on his record like a pretty bogus Victoria class video putting up the same myths about a death trap submarine, a strange schizophrenic anti-AUKUS rant where he went off about how the program should be canceled because he effectively didn't like UK internal politics and worst of all, the one responsible for spreading the nonsense conspiracy theories about the USS Thresher's loss.
I'd steer clear of this guy if at all possible, not good content or quality of character.