It has been tried, and on the whole, it wasn't a success at all: https://en.m.wikipedia.org/wiki/Identity_Cards_Act_2006

Only an extraordinarily confident and popular government would have another go (and it's not what the UK has now).

As for the voting scheme you describe, it's entirely voluntary, for 2018, and no council has signed up yet.

Things may move in that direction slowly, but to suggest that the UK is particularly close to requiring ID for internet accounts is downright silly I'm afraid.