Don't know where you have been but that handheld is ALSO according to Nintendo a home system and as such it's definitely weak.
I'll also add that we are talking about the Xbox one X (a home system) and I added in my comment the PS4 and a PS5 (yet more home systems) so I'm not sure why you did not see that I was obviously talking about the Switch's home system capabilities.
So its weak and doing better than the competition? so why is power important?
Oups, my bad I forgot to say "from the point of view of the consumer" which I assumed you were, which I can tell you I am.
Cause from the Nintendo side, I totally agree with you. Power is the least of their concern, it costs money to engineer a powerful system and if you sell them so well without doing much in that department, why do it?
I also must remind you that this is pretty much what I ALSO said in my first post. I said, "did you hear Nintendo?" Then I added "Of course you don't hear" Then I added, something like "keep doing your thing" as in keep changing the hood but don't bother investing in a powerful engine inside your machine.
Now if you're asking in general and not in the case of Nintendo specifically, the answer is cause more power means better graphics. And before you answer that graphics don't necessarily mean a good game, I'll say that neither do weak graphics. But as a consumer I'd rather good games + powerful graphics than any other combination. Not sure why you wish to settle for a few good games with weak graphics when you could get good games PLUS powerful graphics. (That is if Nintendo consumers woke up and demanded it)
And finally the only question you might be left with asking me is: If I don't care for the Switch why is this a problem for me at all? Well the answer is obvious. If you guys (Nintendo fans) were more demanding and critic of your favorite brand, maybe Nintendo would invest in more powerful GPU's and maybe they would continue making home systems that can rival the Pro and the X. You'd STILL be enjoying BOTW and Mario Odyssey and all those great games but so would more people, you know those who care to see 2017 graphics in those games and not 2010 graphics in 2017 games.