Yes this is specific to the updates Directv streaming put out for Roku but will be coming to other devices. It’s amazing how Dtv doesn’t listen to its customers but doesn’t hesitate to increase its prices. This seems like the perfect catalyst to switch to Sling or Hulu.
I don't have Directv Stream so I can't check this, but ...
In another thread it was posted that a recent update by Directv changed the access key from down-arrow to left-arrow [Edit: BACK key].
LEFT and RIGHT arrows are Channel DOWN and Channel UP, not the guide... These remain unchanged. The only way to get to the guide now is multiple button presses (BACK -> UP -> SELECT)
The way to access the guide and menu now requires you to press the back button at the top of the remote.
AHA! That's probably what the poster I cited meant by "left arrow".