As always your articles are too long for me.
For technical specifications, it goes X1 > Switch > PS4. While the PS4 is more powerful than the Switch, the Switch is more impressive than the PS4. And while the X1 is dragging behind this generation, its console is a modern marvel of technology, you can put the system inside a box and it'll still run cool and quiet. Switch actually runs pretty hot a lot of times, but it runs quiet. On that same note though, the Switch has by far the lowest specs, but the features being packed into such a tiny package is amazing. PS4 on the other hand isn't significantly different than the X1 from a technical standpoint, but the system runs very loudly, very hot, and quite frankly has subpar parts in it. The wireless board that controls internet connectivity cannot handle 5G bandwidths, so over WiFi it falls short. The wireless board that controls controller connections is subpar and almost requires the controller to have a visible line of sight with the system a la the old infrared wireless controllers. Nintendo's Wireless Wavebird controllers (That are roughly 15 years old at this point) are way better than this.
Usability, it goes Switch > PS4 > X1. Mostly I put this on simplicity of use and how quickly you can get into a game. Switch hands down has the simplest UI and no wait to launch a game. PS4's UI is reminiscent of the XMB and games can launch fairly quickly. X1 has a mostly convoluted UI that IS in fact constantly changing, due to how complex it is and users hate it, and games can take hours to days before they can launch.
For libraries and 3rd party support, it goes PS4 > X1 > Switch. PS4 has a distinct advantage with LRG and other 3rd party publishers like Soedesco. A lot of JRPG companies still stick with Sony. Microsoft doesn't have a ton of exclusives, but they still get many 3rd party titles that Sony gets. Nintendo is still having trouble maintaining a consistent release queue, 1 or 2 titles a month just doesn't really cut it. Nintendo looks to be a receiving a lot of games in the future, even some new titles like Wolfenstein 2. If Nintendo can prove their worth and continue getting 3rd party support, they could easily pass X1 in this category.