The Series X|S combined has sold less than half the units of the PS5. I can't find sales numbers on the X vs S, but it seems like a lot of studios have determined it's just not really profitable to do that level of optimisation unless you can also squeeze the game onto Switch, which does not have as much overlap in demographics as the Xbox and PlayStation do.
The article cites Larian having similar issues with Baldur's Gate 3 and Remedy with Alan Wake 2. This isn't just one shitty lazy dev studio- this is Microsoft forcing hard decisions on devs by insisting on walking the Series S like they're in Weekend at Bernie's.