Considering the early success of Switch, and Nintendo's recent history of upgrades mid-gen, and the new industry trend of doing the same, I think it is very likely that Switch will pass XBO at some point. But, that may simply be because Switch lives for a long time, as opposed to passing it with 3-4 massive years of sales of the original Switch hardware.
XBO, while it hasn't been a failure by most standards, has definitely not been a sales beast. So, beating it is probably not the goal Nintendo has in mind for Switch. I think they want a lot more than that. Whether they will reach a more lofty goal, let's just say 85 million units (because I need some number), is far less certain (though certainly not out of the question).