Henry absolutely should be paying more tax to help support Ethel. I don't disagree. But people saying that Henry should just move up North so he can buy a house for 120k are missing the fact that that means Henry will take a big pay cut and be paying less tax. And the UK needs the tax he pays to support Ethel. Plus if lots of Henries identify an area where they can do that, and all start to do that house prices will sky rocket and Ethel won't be able to afford a house, and she'll complain.
Yes, speaking as someone whose household income is less than 100k and still lives a pretty nice lifestyle up north, actually it's very much in my interests that Henry and co stay exactly where they are, eat up the batshit housing costs and marginal tax rates.
If he were my friend, I'd tell him unless you really love London or are getting something out of it that you need and can't get elsewhere, get on your bike and look for work up here/do the job remotely. My loved ones deserve that advice. But actually, I wouldn't much like the consequences if enough of him did that and I suspect neither would a lot of the people suggesting it.