Chaosmancer
Legend
Hardly an exception. Absorb elements requires that I take damage of specific types. How do I know that the damage I took is cold damage?
Or heck Silvery Barbs. How do I perceive that a person passed their saving throw? If a person passed their fireball save but still died from the half damage....do I know they passed? If I hit a creature but do no damage due to a damage threshold, do I know I actually hit?
There are very few reaction spells in the game, and I would argue a good portion of them get really hard to use if you truly require the caster to understand and perceive the trigger.
Agreed. There are a lot of reactions that require such a precise amount of awareness that, honestly, if you over apply the concept, you end up with many abilities that flat do not work.