They didn't report the numbers (in any meaningful way) because Elon likely thinks it's stupid. Just like everyone else does.
Everyone? You can count me out of everyone. You think the folks at the DMV behind this program think it's "stupid"? I think you could find somewhere between 10 to 60% of people who have at least looked at the numbers who think that it's not the end all be all stat BUT yet not totally worthless, esp. if additional context is provided (e.g. about the routes, conditions and environments that testing was done under).
Disengagement Report 2019 had a summary and calls out Baidu.
As I've said before, Tesla's all about hype. If their system was doing so well, they should have no problem demonstrating a high # of autonomous miles driven on CA public roads w/a low disengagement rate (up there with the top 5 players) and improvement year over year. Instead, they turned in years of big fat 0, ~550 miles with a horrific bunch of runs and somehow a clean run during one year, more 0 miles and now 12.2 miles.
If they were really doing well, they should be doing their testing in the streets of San Francisco but have more miles covered, a better disengagement rate and lower accident rate than Cruise Automation.
It shouldn't be difficult at all for them to collect and track the info that the CA DMV requires. If they can't handle it, then what does that say about their progress and readiness for customer deployment esp. about the mythical robotaxis in the timeframe that Elon's talked about?
At least it seems like many (most?) companies are complying but if Tesla is just skirting the law or willfully violating it, you think that's going to look very good in the eyes of CA and other state regulators? CA DMV could pull their permit. I'm not a lawyer but perhaps they could even sue Tesla and others not in compliance.