I appreciate the purpose, especially in uses where you just need data access, but have to agree with others that it's not for me due to lack of upgradeability, low performance, serviceability, and probably lifespan too if it depends on a shorter lifespan small/thin fan for cooling (else it runs hotter and has lifespan suffrage more continuously instead).
I suspect that "eventually", we'll have sufficient functionality in our phones, and monitors will have built-in, or a small add on module with HDMI or whatever the next standard is, for wireless communication between the two. We do already have the tech to do this but the performance of the host and the bandwidth of the wireless is still a bit lacking for a large scale deployment, particularly with the push to keep increasing monitor resolution to 4K and beyond. Granted, that res. isn't really needed for many data access purposes, but can't hurt either.