I can agree more.
Ive upgraded my setup having in mind to keep it for a while, so I went with a atmos 9.2 Onkyo 4k receiver (used on FB @ 300$), so even those stuff are starting to be on used market annndddd not much content yet.
Got a 4k projector, BenQ HT3550. Right now I have a 7,1 setup. Acoustic pannel on my walls.
HTPC is a surface pro, minidisplay port, 2016p setting. So I'm sure it can play 4k and decode all type of audio format.
REady to have full experience, and no content hahahaha
But microsoft market got a software for dtx and atmos demo, impressive , but this was my 1st and only experience.
Also, most TV provider wont give 4k, its 1080p or even 720p upscaling.
Sad to say, but my 2007 setup on my 1st floor still up-to-date ! A old Sony 55'' bravia II 1080p (3'' thick, old LCD tv, one of the 1st affordable 55'' on the market back then, 1800$), and a simple Logitech Z680 5.1 surround. PrologicII do a sweet job converting 2ch to 5.1.