I voted yes. Every Xbox game should be multiplatform.
Because Xbox users do not buy games. Hi-Fi Rush was ranked 207th or something (according to Circana.)
But of course, the die hard Xbox fanboys would never admit that going multiplatform would be the best thing for Xbox.
Clearly, having the software go multiplatform is not good for Xbox. It may or may not work out for Microsoft as a game studio. Arguments could be made that Microsoft would make more money on the games if they were available on other platforms. The counter argument to that is that they make more money on GamePass, and if they lose the players from their own hardware to Sony and/or Nintendo, those players will no longer be GamePass customers, so they could hurt even their software revenue.
But regardless of effect on software sales, obviously Xbox sales will be worse without the exclusives to bolster them.
The ONLY strategy I can see that has a chance at helping Xbox sales by going multi-platform is with long delays (timed exclusives). Then, MS could get players on other systems interested in its franchises (as they gain access to them eventually), and hope to lure them eventually over to the Xbox ecosystem for faster access to the new entrants in those franchises. Big fans who don't want to wait 1 or 2 years for access to a franchise's new release MIGHT move to Xbox.