indeed, it's silly to go for 4K for the reasons you all said:
1) incredibly big raw files to work with, editing and rendering time increase more than 4x
2) upload time, even with Dave's super fast new uplink, you're talking at least 2 to 3 times the filesize thus negating the benefits of the fast upload!
3) WHO has 4K, practically noone, you can have 4K TVs tight but how many EEV viewers watch it ona TV instead of a PC?, hell, i'd say that more than 90% don't have a monitor that's bigger than 1080p....
4) For those that use TV/HTPC, there are no commodity HW decoders that can handle 4K decoding right now except for the latest haswell/nvidia/ati GPUs, a raspberry pi or HW set top box won't cut it(so you can have a VERY modern ivy bridge pc/htpc/notebook and you won't be able to HW decode and if your cpu is one of the low end ones you won't be able to SW decode it without dropping frames).
5) for PC use/gaming there's no GPU that can handle gaming at 4K (you need to invest in retarded double/dual GPU that costs thousands of dollars to even reach playable performance) and the benefits on "small" screens is iffy with the issue of DPI scaling
6) Cost, retailers can plaster their walls with 4K TVs all they want and ofc they're going to do that since they have a ridiculous overprice so by filling their space with those TV they generate unneeded hype, until a decent brand(LG, philips, etc) 4K set becomes cheaper than a current 42"(that's the sweetspot size) 1080p (no smart, just plain old TV) then the technology is dead to consumers, just like the 3D "fad" that ended up in utter failure (and why do you think they push 4K...)
7) Content: there is no compelling content and practically no reason to go to 4K, CATV is not 4K ready, i wouldn't even watch 720p on DirecTV their sats just don't have the BW, they have a ton of compression artifacts even in the SD content, very noticeable on dark gradients even on a CRT(i had DTV since day 0 here until i dropped it due to excessive cost and the vid quality was horrible, very noticeable on blacks).
I've seen DTV in "HD" they have 2 or 3 channels, and it's 1080i only, terrible.... Also majority of "old" BD players don't support 4K, even current gen consoles cannot playback 4K BD AFAIK.
In fact, CATV HD channels are 720p!, we're not even using 1080p widely yet because of filesizes and diminishing returns!
so yeah, 4K is useless at this moment, and will probably continue to be so for many many years, it's not like the SD to HD(and on a small measure to Full HD) transition that did bring massive improvements in all aspects, fHD to UHD doest not really bring anything tangible to normal TV sizes(up to 42") (and who cares about plutocrats with their wall to wall TVs next to their Mercs) and has all drawbacks