I also think X is irrelevant when it comes to next gen consoles.
It's a niche product aimed at those who want a premium experience out of their Xbox One games, nothing more (same with Sony and the Pro).
X owners should have known what to expect when buying it.
The problem is if the core fans (early adopters) keep getting burnt. For example;
1) Kinect 2 was forced upon the early adopters then dropped
2) The machine cost more than the more powerful PS4 meaning the fans suffer the weakest versions of games
3) MS release the X1s which gives a minor performance boost so that core upgrade
3) A year later MS release 'the worlds most powerful console' to appease their fans - again hardcore upgrade
4) Less than a year after the launch of X they are talking about their next console
5) 2 years later they release next gen (potentially 1 year later if people truly believe MS would launch with Sony if PS5 was 2019!)
6) That console launches meaning the core fans have purchased potentially 4 consoles in around 7 years
I do get what you are saying, but it's a fine line to walk...and each console have been significantly more than the PS4 equivalent, assuming X2 is $500 that's ~$1780 over the 4 consoles vs the $1200 of the same upgrade journey on PS.
Maybe I'm thinking too much into it though...I just don't think it should be totally ignored, I for one would not be happy to have a bi-annual upgrade-a-thon.
