A UHD drive isn't cheap at this point and it also greatly reduces both power consumption and thermal requirements (so they can use a cheaper cooling solution - especially compared to the elaborate vapour cooling solution they currently use in the Xbox One X).
Also means a smaller console with reduced manufacturing complexity. Those savings all add up pretty quickly. Add on the fact that all purchases would be digital, meaning greatly increased software margins, and it offsets the manufacturing costs a lot more quickly for MS (meaning that they can afford to drop the hardware price to compensate).
There's a user on here, Intersect I think, who can go into greater detail on blu ray costs.
But that also means two different consoles to make so even if the disc less console is less complex to make you now have two variants to manage. Seems like that would negate any reduced complexity.
In 2016, IHS estimated the UHD drive in One S cost $33 compared to the $18 it cost to make a standard BE drive. I can only imagine that price has come down
In fact you can find UHD players on sale for $100 often at stores. It does not cost much more than $20-$30 to add a UHD drive. The impact it would have on price is minimal while the impact it would have branding and consumer Confusion over SKUs could potentially be large
$100 UHD players (just search Best Buy's site) are probably sold at triple or double cost to make profit. If so, i doubt a drive costs much to make
