i mean, doug demuro doesn't know much about cars either, but he's amassed a massive cult following. tavarish cuts as many corners as BIFB, if not more, but on considerably more expensive cars, and he's got a big cult following. one of the TFL guys- i think nathan- has a rep for showing up drunk to press events where he's supposed to be driving cars.
car-tubers don't get big because they're good with cars- they're just good at "playing the game", and generating a boatload of content in small windows of time to maximize profit. there are a good number of smaller channels with encyclopedic knowledge of their vehicles and a general commitment to doing things as correctly as possible, but i guess you can't do that when making content is your job and not your hobby.