Considering that there's about half as many Nintendo Switches in customers hands after only 6 months as there were lifetime Wii U sales, even if only 1/5 of those people bought a copy of DOOM on there (very wishful thinking, I'm honestly only expecting 1/8 adoption rate at the highest), it would still be as good of sales as the Xbox One version alone [DISCLOSURE!: I am basing these numbers off of ******** stats. These numbers are not up to date and do not account for digital version sales!]. It helps that a few of those people are going to buy a Switch just so they can double-dip on this (hell, I've talked to people who said that the only reason they want a Switch is for portable Skyrim), but it also helps that Doom's campaign was freaking amazing and got spread about by positive word-of-mouth.
Bethesda is definitely seeing this as "fast adopting console+popular game=easy money."