I just leave restaurants that have gone to the online-only menu. It's usually an indicator that there are other terrible cuts in service and quality going on as well.
I leave because I go to a restaurant to enjoy a meal with my family and friends and to connect. Forcing everyone to stare at their phones for the first five minutes is a bad start.
I’ve thought of this - if there’s no paper menu available, to avoid tracking, I always just search for the restaurant and navigate to the menu from their webpage rather than using a QR code.