[Technologist]

It’s estimated to take another ten years or more  to get Wifi speeds across the country to all be fast enough for streaming to work in every house.

I think you mean Broadband not Wi-fi ......
But the UK currently has only 1.3% properties unable to access less than "Decent Broadband" i.e. the USO
www.ofcom.org.uk 
that is smaller than the number able NOT to get PSB DTT TV!

That Document discusses how this will be reduced - but does not mention that the Major telcos will offer 30Mbit/5Mbit?
as their USO product - which is ample for streaming
i.e like the 97 % who can already get better than this! (comparble with Freeview lite and Less than DSAT coverage)
Or the 75% on "gigabit capable" ( 52% Fibre rest Virgin DOCSIS)
But there is more work needed in Wales and Scotland ( NI has more Gigabit capable than England!)

But wiring equipment will improve things!!! and reduce Wi-fi interference