I've noticed this.

On an sCO 764 yesterday EWR-IAH, the FA didn't make the "you can now use electronics" announcement until about 15 minutes after leveling off at 32,000 ft cruise.
They only had 2 runners serving drinks to the 39 seat cabin, so the drink service took a while. The meal service didn't start until over an hour into the flight, maybe trying to push it closer to normal meal time (3p Eastern departure, 630p Central arrival).