It was a 21 minute video with some interesting detail. They discuss how difficult it is to get all the data from an individual vehicle. Tesla tells you that you can download your own data, but they don't provide all of it, such as what FSD was doing at any particular time - Tesla withholds that info. All of the data, however, is transmitted back to Tesla but for the normie/owner to access it, they'd have to take apart the dashboard to access the computer and then hack it. WSJ found a guy who likes to work on wrecked Teslas. He pulls the computers and then sends them to someone who hacks it. Even though they only have 6 cameras, there's a good chance they're not synchronized, so what one camera sees can be totally different from what another one sees. The example an ex-Tesla employee gives is that an un-synched camera can make something look like it's floating in the air.
This is a 3.5 minute portion of the full WSJ clip that discusses how the reporters accessed the secret data. It has an injected ad or two that you can skip after 5 seconds. https://www.msn.com/en-us/money/news/how-hackers-and-mechanics-unearth-tesla-s-hidden-autopilot-data/vi-BB1qRxcX