There are 100k people beta testing this, so you'll find any kind of situation imaginable on Youtube, whether downtown NYC, torrential downpour, weird intersections etc. Many Youtubers find edge-cases or difficult routs and then drive that same route for every version to see how it improves (or not). Chuck Cook's famous unprotected left turn is one of those that got (mostly) fixed this release.
> Is the hardware different, or just the software?
It's the same hardware, just software and deep learning improvements. There are higher resolution cameras and better inference hardware coming out, but they're claiming it's not necessary for full autonomy. My guess is eventually they'll hand it out for free just to avoid supporting old hardware. The current cameras are quite low-res.
> Is the autopilot preview meant to help sell FSD?
No idea, but I hope they change it to FSD visualizations soon. For a while they've been trying to join the stacks for freeway (AP), city streets (FSD) and parking into one, the famed version 11. Since AP has been using this old stuff that's probably why they use these visualizations.
And to be clear, this is definitely not done, requires constant supervision. But it's improving pretty fast.