Looking at Mercedes is foolish IMO. There's no reason to think they have any expertise in this domain. They have some press releases but very little technology to show for themselves. Cruise and Waymo are the other major players here.
If they're taking a measured approach, and it's working, then it seems like they've either bought in the expertise or managed to develop it. :)
And taking legal liability in very narrow (essentially useless) circumstances is exactly why it’s a marketing thing. It’s to make it seem like they have an advanced system when there is no evidence of them having it or having any realistic path forward.
After reading that, it's hard to tell what Mercedes is doing. :/
Hopefully it's not just marketing bullshit, but I guess we'll all only find out over time.