You don't even have to leave London to see a night and day difference. I currently live in a new-build flat and have multiple choices for fibre (Hyperoptic are great). I am hopefully soon to be moving less than a mile down the road into a house where my choice is either an offensively slow BT-backed service or an offensively unreliable (so I have heard) Virgin Media service.
If you have a new-build flat in a major UK city you probably have a similar decent choice but the rest of the housing stock (the majority by far) is stuck with BT/Virgin.
You'll almost certainly be getting BT FTTH in the next year or two if you have access to VM. The program is running quickly, something like 6 million premises a year and ramping.
VM can be ok or can be congested depending on the area. BT FTTH doesn't suffer from congestion issues (nor does the FTTC).
Check https://bidb.uk/ for more information. It collates all the altnets and planned roadworks into one dashboard.
>> BT FTTH doesn't suffer from congestion issues (nor does the FTTC).
That is just not true. BT consumer FTTC is contended up to 40 to 1--that is you are sharing your backhaul with upto 40 of your neighbours. I am assuming that their FTTH services are the same.
If you have a new-build flat in a major UK city you probably have a similar decent choice but the rest of the housing stock (the majority by far) is stuck with BT/Virgin.