I'm not sure if technology will be to that point by that time to make a convincing handheld with Xbox One X graphics abilities.  The main reason Switch was able to do it is because Nintendo came in at the right time with tablet technologies and compromises on the graphics due to the competition.  It was a very intricately designed device, very specific in how it was positioned.  I'm not saying it would be impossible for that increased price point, but one reason Nintendo was able to do it was in part due to the status and conditions of other markets. Eventually graphics capabilities will become a mute point and anything will be accessible, but I think that merger is still a ways off.  I'm sure they could create something to directly compete with Nintendo though in some way.