This is only a relative argument if you can prove the government accurately and granularly represents the population. That would be nice if it were true but speaking as an American, I find it hard to believe.
Keep in mind that our voting system is actually built so the parliament represents the popular vote as closely as possible. It’s not just an assembly of winners of individual “winner takes all” decisions. The average being above 0 in the graph should indeed mean left parties would be in the majority more often than not.
Edit: Another comment reminded me that the graphs only show 18-29 year olds. That explains it somewhat.
This is only a relative argument if you can prove the government accurately and granularly represents the population. That would be nice if it were true but speaking as an American, I find it hard to believe.
Keep in mind that our voting system is actually built so the parliament represents the popular vote as closely as possible. It’s not just an assembly of winners of individual “winner takes all” decisions. The average being above 0 in the graph should indeed mean left parties would be in the majority more often than not.
Edit: Another comment reminded me that the graphs only show 18-29 year olds. That explains it somewhat.