DSR if I remember rightly, renders at a higher resolution and then downscales to what your native resolution is. You should be able to enable it or disable it, but you'll never get it to display more pixels than you have. I could be wrong also.
Right on Respawn and Geforce's website is says that Titanfall 2 supports DSR. No it doesn't, I am unable to go anything beyond 1080p (native).
Am I missing something?
No problems with 3840 x 2160 (native) high setting here.
Exactly, because you're running 3840 x 2160(native), which means you have a 4k display.
My display is 1080p
I'm talking about what jossrik is, where your GPU renders the game at a higher resolution than your monitor can display but downsizes it, it effectively does what anti-aliasing does but better. And DSR works in every game I have except Titanfall 2 despite Respawn and Nvidia's claims.