It is truly sad how many devs now have us port begging for games on Xbox. It shouldn't be this way, as a developer or publisher you are supposed to be capable of doing your own darn market analysis to see if a port is viable. Spoiler alert, most ports will turn a profit on Xbox unless it's either a very small indie dev with very limited development resources or a super niche genre JP game like visual novel or schmup, basically everything else is capable of making a profit these days due to the reduced porting costs brought about by Xbox and Playstation switching to PC based consoles starting with XB1/PS4, and moving even closer to PC with XS/PS5. On a small indie it probably only takes a 2-4k sales to turn a profit on the port, a bigger indie more like 10-30k sales, a AA probably 40-60k sales, and a AAA probably 150k sales at most in most cases, the more it sells over those rough break even margins the bigger the profit on the port.
A double-A Souls-like such as Phantom Blade Zero should easily be able to clear that break even point, as popular as the Souls-like genre has become, pretty much all of these Souls-likes that have reviewed even decently have sold alot of copies.
I think the big problem with this is that when it comes to porting costs, everyone assumes it doesn't require a lot of resources simply based on development resources. That's a big mistake. Yes, development work on creating an Xbox port from existing PC version doesn't require a lot of dev resources most likely. But as someone who works in software development (not gaming related tho), let me tell you that QA efforts quite often take half of what is estimated for development and maybe sometimes even more. When we take ports in consideration, QA efforts don't decrease for Xbox port and in realistic scenario they should be the same for every platform. So, my guess is that the problem here is investing in QA for Xbox port, not development. Maybe you'll be fine if devs will just throw out Xbox ports without any testing at all, but I surely won't. We have enough of broken mess games already.
P.S. Not sure what your calculations are based on, but to be honest I have some doubts that any game can be worth investments just to sell 2-4k copies