Just count yourself lucky that you don't have an Exchange Only (EO) line, that doesn't have a cabinet and runs directly to the exchange.. I'm in Whitechapel (Zone 1) and get 8/1
It would be technically easy to give you VDSL, it would just break a rule that was put in place to ensure competition for ADSL service, which you now don't care about because even that close to the Exchange it's only giving you 8/1
He uses a 4G router with a Three unlimited SIM.
He has both connected because we do a lot of FPS PC gaming and the latency on 4G is too poor to game so he switches to his ADSL connection to play games and then uses 4G to download/stream.