Just saying that train drivers pay isn't associated with how productive they are. Across the board you would certainly hope that wages keep up with productivity.
My point was that the data suggests strong reason to believe that real incomes have decreased broadly by a very substantive amount in Britain in the last fifteen years. A rail worker should look at that and say, "I'm doing the exact same work for much less pay. This is nonsense." Off the top of my head, I cannot think of
any genuinely democratic country where that sort of decrease in real income did not ultimately lead to a transition of power, and much sooner at that.
I went looking for income and GDP data for the obvious comparison case (Germany 1918-1933), but I don't think it exists. The St. Louis Fed only has GDP/GNP data back to 1947 for the U.S., income data is limited by the existence of an income tax, and everything written about Germany at the time seems to use proxies (and bad ones) for income. It doesn't look like Piketty has data, and I would think he would if it a means of compiling it existed.
I don't see how those data points can coexist with the Tories holding power for twelve years
and Freedom House scoring Britain a 93/100. That flies in the face of absolutely everything I know about democratic politics. The best explanation I can come up with is that you can hold onto power for a long time if you calibrate boiling the frog just right, but even that doesn't work with an actual frog.