There are significant differences in language and purchasing habits between the countries. In what sense are the UK and France the same market when they use a different currency, a different language, and have wildly different taste? Just look at the relative performances of Nintendo and Microsoft in the UK and France.

Take, let's say, Quebec and British Colombia. They have different language, different taxation structure, and different tastes. I would also expect similar gaps between the Midwest, West and East coast of the United States. 

It would make sense to seperate the UK, perhaps - they have different currency, it's an island, and people don't travel as in consequence. But mainland Europe is, to me, too interconnected to be seperated into several different markets. If you look at France and Germany, taste is actually fairly similar.

Working on that...

Shouldn't we discount the Wii U by now like Nintendo has? If so the UK is still quite a bit bigger.

Well that is not the only reason even the PS4 in Japan is outselling all of the console sales in UK currently

There is a thing called the EU though which is pretty much the United States of Europe these days.

I know. Just saying. 

The wii u has been dead for a while now so shouldn't be included so Japan is still behind the uk for console sales.

Wait, the difference between UK and Japan has WORSENED with the Switch? UK has sold 22,4% of japanese number of WiiUs, but only 17,% Switches. And Switches in Japan are supply constrained, while they aren't in UK. This actually blows my mind.

Not really, overall it is better. But this means the UK liked the WiiU more than the Switch.