I am quite surprised by the amount of negative comments here. My immediate reaction after watching the video is that this is pretty cool and I want to try it, even though I expect issues given that it is the first service of this kind in London.
Personally I wonder why didn't they put several Pater Noster parking machines instead.
Systems with eight slots have decent throughout, the same density as cars parked side-by-side and bumper-to-bumper - even including the space needed to roll out - and are mechanically simple compared to just about anything else in this space.
Replacing "hand over your keys" with "perform detailed inspection of your vehicle, including undercarriage and suspension for damage before leaving" doesn't sound particularly enticing. Given I'm capable of parking my own vehicle without having an anxiety attack in the process I'm also fairly certain this thing doesn't solve any of my problems. I am likewise surprised that this seemingly pointless, grossly overengineered system that is nakedly hostile to minimum wage tier workers like valet service drivers isn't being warmly received here, but for different reasons.