Not everyone has a 4k TV yet. I don't have one yet myself, but when I do (later this year) I can utilize the Shield immediately without having to get another device.Future proof against what? 4k? All these devices will be close to obsolete in a couple years anyway. That's just how it is. No device is truly 'future-proof'.
At $200, IMO, it is overkill as just a Kodi device.
All the other devices that run Kodi just as well are $100 and under.
If you're a hardcore gamer as well, then I could see it being a good buy.
Nothing is obsolete so long as you still use it.
It's main function isn't KODI, it's an Android TV device, that also gives the option to run a ton of other apps.
That, to me, makes it worth it.
And I originally paid $199 for it but ended up spending $149 (plus free remote) after they lowered the price.
It's worth it to me and others. Hell, the reviews against comparative devices (Roku 4, AppleTV, Nexus Player, FireTV) has the Shield typically smoking the competition.