Leaving Plusnet becasue I can't get FTTP

[#1]

BT wanted to fibre up the UK over a decades ago.
They were prevented by the government at that time who feared it would give BT an overwhelming lead as the government wanted to encourage competition from other suppliers.
What we got instead was the cable companies who provided a superfast cable supply to the the "low hanging fruits" of the urban areas only and then promptly went bust.
Edit:
Then there is that Fibre only exchange experiment/trial (FOX) at the Deddington Exchange in Oxfordshire BT are quietly running.
As to lowest cost - no they changed part way to ECI to indeed get a lower spec lower cost cab at the tail end of the commercial roll out where I guess margins were tight on whether areas were going to be profitable.
It bit them badly as the ECI's were not as capable and as upgradeable as the Huaweii so they are now in a mess where ECI's were fitted.
So BT has gone back to their original preferred supplier - Huaweii.

[#2]

Quote from: sarczoid

So essentially the only people who defend BT are the ones with FTTH at home, (sod you jack, i'm alright)

No one is defending BT, rather simply trying to illustrate that comments such as this...

Quote from: sarczoid

You do realise that FTTP will never happen as long as BT have a stranglehold over the UKs broadband infrastructure.

are ill informed.  BT Openreach IS deploying FTTP in a number of areas across the country, some in places where FTTC is not being provided as an alternative, which is the issue the OP has.

[#3]

If people can't get FTTC (me included), how can they offer FTTP as an alternative when they can't fork out ~£30k to upgrade a cab for FTTC? FTTP must be more expensive to install surely?

[#4]

Well that all depends....
It is inevitable due to the time it takes to roll out technology that some locations will get left behind.  When their turn comes, they 'leap-frog' onto the latest technology.  In the area I'm aware of (not mine) they never got ADSL2, there is no FTTC, the area (small village) is going straight to FTTP (premises).
In some areas, all new builds are getting FTTP.