For things like sauces or marinades, you use a much smaller amount, and approximate is generally fine.
To be clear, I'm not disagreeing with your general premise, everything would be much easier if all recipes used weights for powder-like-ingredients. But recipes that actually have weights listed are few and far between, I find.
Every recipe on King Arthur that you linked has weights.
I realize how I sound, but there is a very big difference in a couple of percentages of flour, and you'd definitely mess up a beginner with the difference with the amount of flour.
Especially for bread where saturation percentage is important, weight/mass measurements is absolutely necedsary.