Mr. Speer does really terrific work but on the fundamental question of a conspiracy, which he believes happened, he is flailing around. He admits that he doesn't know who shot JFK, who the shooters were. That is, he doesn't know whether it was the CIA or the mob or anti-Castro Cubans or some combination of them. Or even some other group. Fine, good for him for admitting this. Very few conspiracists say "I don't know."
But he says he knows with "100% confidence there was a conspiracy"? He knows this? So he says he has no idea who the shooters were (he's absolutely sure Oswald wasn't one of them) but they, again whoever they were, were working together? How can he know this with 100% confidence? Obviously, as the HSCA said, if there was a second shooter then JFK was "probably" killed as a result of a conspiracy. But "probable" is not 100%. That sounds pedantic but I don't think it is.
The problem is, you put all skeptics of the LN narrative in the same bucket as "conspiracists".
It's perfectly reasonable to note the inconsistencies and problems with the JFK assassination investigations without speculating about the identities of the shooters or the mastermind of the conspiracy. To be a "conspiracy theorist" you have to have a "theory", not just mere skepticism about the Warren Commission's conclusion or other investigations.
Speculation is fine so long as you're honest about the fact that what you're claiming is speculative and not proven.
But avoiding speculation while just focusing on the facts is a more respectable stance.