"competing infrastructures to drive down costs" ?
"having 40-60% of the populace covered by two systems whilst the rest are covered by none seems a bit silly."
Correct, though actually it's far far worse than that. TV these days is just a stream of bits. Same for phone. So some areas have the following overlapping options, incurring unnecessarily duplicated costs, because our leaders are in awe of The Market:
. BT phone
. BT (non-LLU) DSL broadband
. non-BT (LLU) DSL broadband (separate non-BT kit at the exchange, separate core network)
. Cable phone
. Cable broadband
. Cable TV
. Terrestrial TV
. Satellite TV
. Satellite broadband
. Wireless broadband (where applicable)
In a joined up world one universally available fibre to the premises could replace all of these; how much would that save on infrastructure costs?
So rather than "the market" driving down costs, all its doing in terms of broadband is slightly driving down end user prices for a service which ends up being connected to several sets of unnecessarily duplicated exchange kit and backhauled over several unnecessarily duplicated ISP national networks. Similar argument applies to cable (be it phone, or broadband, or TV) and satellite (mostly TV only but occasionally broadband).
Put history to one side for a moment and think about the cost savings (and the new opportunities for users, service providers, and indeed for content providers) if we had a properly designed properly managed properly regulated (!) access network.
DSL broadband is for dinosaurs, especially so for BTwholesale DSL.