I would expect that they have access to the cameras of all Teslas on the road, which should be about 5 million:

https://www.statista.com/statistics/502208/tesla-quarterly-v...

And I would expect that those generate more data than they can crunch, so that the bottleneck is the number of GPUs they have.

They recently reported that they have the equivalent of 40k H100 GPUs:

https://twitter.com/marekgibney/status/1784133742983860307