John Derbyshire regularly makes the point that in Europe, what defines Right and Left is not economics, but immigration. The only reason they continue to use the old terms of “right” and “left” to describe the mainstream parties is habit. While there are some differences of opinion on economics, foreign policy and regulation between the German CDU and the SDP, for instance, those differences are trivial.
The real difference between modern mainstream parties in Europe is the aesthetics. This is expressed in the leaders they choose. It varies from country to country, but usually one side prefers a Cavalier and the other a Roundhead in terms of presentation. Otherwise, the parties agree on all the big stuff, particularly immigration.