On AppleTV, if I want to see the time, I just long press on the TV button — Time and date smoothly slide in from the right. A tap of the Menu button slides them back out — unless I realize it’s way past my bed time and instead press the already highlighted Sleep button to turn everything off.
If in the middle of watching a program, you can tap the time-bar to toggle between elapsed-time and time-remaining with current-time and the-time-the-content-ends.
Ah, Firecore already commented some time ago about the first option I listed.