Fboab’s picture doesn’t look like an 800 to me.
It's got a Crosscountry Voyager (Class 220 for those playing along at home) aesthetic.
So there's more than one type of UK train with silly bike cupboards?
Oh yes. Crosscountry
[1] Voyagers have had them for ages, and unlike the 800, cupboard access is from the front, rather than the side, for extra impractical cantilevering and reduced handlebar width.
Here's a wider-angle view with a low-racer for scale
[2]:
The opening of the cupboard is approximately the width of a set of MTB bars. It's supposed to accommodate two bikes, and if they have drop handlebars it mostly works, but it's a serious game of Sokoban (requiring other train users to stay Out Of The Way, and therefore impractical at busy times) if you're not both alighting at the same station. Also note the space between the back of the cupboard and the bulkhead with the doors to the seating area. This is a generous 'bulky luggage' area, from which cycles are expressly forbidden.
The reason you're hearing about dangly bike spaces now is that lines that go to That London are getting Class 800s.
Dangly bike spaces can also be found on
Virgin Avanti West Coast's (220/221) Voyagers. These are slightly less bad, because:
a) They're not enclosed in a cupboard, so the lifting is easier
b) Unlike the (390) Pendolino (which has an excellent ground-level tandem-compatible bike compartment), you don't have to track down a member of staff to gain access to the relevant compartment
c) They're consistently at the non-London end of the train, rather than halfway down from the end that doesn't have a yellow bar above the coupler
I believe there are/were some HSTs out there with dangly racks in the guard's van. The one time I encountered one I just shrugged, engaged the parking brake and strapped my heavily-loaded bike to the wire mesh wall of the compartment.
[1] Who, as the name suggests, run most of England's useful long-distance services that avoid London.
[2] This photo taken on a return trip from Mordor to Wolverhampton for the express purpose of determining whether this was possible.