I really don't think your argument makes any sense at all. The fact that a quirk of history leaves us with creaking and outdated broadband infrastructure does not mean we are insulated from those countries in Asia and Scandinavia that don't. It's like football team only comparing its performance to teams in the bottom to middle of the league table instead of the top 5 teams. Its a distortion of reality.
The stats you mention are again shifting very quickly. Unless we move to more than barely incremental infrastructure updates we will inevitably slide downwards irrespective of what stats we choose to measure ourselves against. The other effect of incremental infrastructure upgrades are that they make it ever more costly and unlikely that we will ever catchup or overtake the broadband speed leaders of the world.
The world is one big market even more than it has ever been and we compete as a country with countries in Asia just as much as those in Europe. We need world class broadband speeds otherwise we will increasingly not be able to compete with other countries in any of the new digital industries or even in the old ones.