The UK is the fifth largest economy on Earth. If we build a better internet, don't you think that every sensible country in the world who wants to collaborate and do business with us will find a way of connecting with it? Surely the British Commonwealth will breathe a sigh of relief and abandon the American led domination of the internet and flock to using our version. Even sensible Americans will prefer our internet over their slower one. We can probably assume that the largest trading block in the world, the EU, will stick with what works for them, but then they're not British and don't care about what TV our children watch and whether Amazon works from Iceland or not. In time they too will realise that the British internet is better than the rest of the world's and will beg us to use it.
We don't want our lives controlled by people we didn't elect and who don't care about what the British people want. We're big enough and smart enough to build our own, superior internet.
A British internet for British people! Let's make Britain great again!
...or maybe we should not be so incredibly stupid, and continue to make the best of an imperfect system that works, despite not controlling how it works. I'm IN (in case you hadn't worked out I'm parodying arguments for the UK leaving the EU).