What I mean is that people today call the Switch "gen-8 console" which would automatically make it 2nd place of generation 8. But I'm willing to bet that by 2021 people will start calling it "gen-9 console" which would automatically make the X1 fall into 2nd place of generation 8.
Ah, I see. Either way we slice it we can say that the Switch outsold the XB1 in three short years. I think gapchartz, done by this site, will show that neither XB1, nor XB2 will be able to keep up with aligned Switch sales.