I think the fact that Justin defaults to that annoying radio DJ tone/intonation shows that he knows (consciously or unconsciously) that he is a toy salesman, and hence goes automatically into sales pitch mode. Like an ad reader on the radio.
I'm an Australian and I can guarantee no-one talks like that.....except the guy reading the competition on the radio to win something.
If he talked normally I'd watch all his videos.
For now Jedha Patrol and Man of Hot Collectibles are my reviewers. Although Man of Hot Collectibles slips in a few Justinism's from time to time. I notice them immediately and switch back to Jedha