A worthy discussion could form around this clip with a potential parallax view of correct analyses.
But at the end of the day, people who have mental issues rarely convert to Buddhism or Judaism etc. and then exhibit threatening behaviour in this way. People who gravitate towards hostile behaviour, recognize the inherent justifications for murderous actions in Islam and gravitate to it for very rational reasons, even if their own psyche does not ride comfortably with reason at that time.
So while I can’t blame Islam for this mans actions, I do not think they are motivated by jihad in the ‘normal’ sense, there is a very real and very important connection between Islam and what he did.
It was the justification for what he wanted to do anyway.
And the why of that, is what matters.