I don't understand why is it so difficult to understand.
Howden is a center and PKer. Other things being equal in case the Rangers need an in-game "emergency" center and / or PKer - it's Howden over Gauthier. Plus, whether you want to accept it or not but the difference is also that Howden has had more experience compared to Gauthier and with head coaches - it counts; unlike the hockey boards where hypothetical potential worth more than actual experience. And also there are degrees here - we're not talking a gap in talent between Kravtsov and Blackwell. We're talking frcking Gauthier vs. Howden!
Howden doesn't really take faceoffs and is bad at them anyway, and we have plenty of PK options. As a stand-in centre in case we really need one, I mean, I guess, but that's barely on my radar as a legit reason.
It's that experience/familiarity argument that is most likely the reason that Howden gets the nod, as he would from any coach, but I don't see either of those reasons as being justification to play a worse player. Also, Gauthier is more prone to unpredictability; not something that is going to earn a coach's trust.
But Gauthier SHOULD have gotten more opportunities, I think everybody agrees on that. And my personal preference would be that he gets opportunities now as well. Even if playing Howden or Gauthier on the 4th line "doesn't matter" (which I don't agree with), then I would still prefer to play the better player.
But I'm not upset at all. I don't understand how the argument has been going on for so long, because as you say, it's frcking Gauthier vs. Howden.