In the latest Developers Discussion, miHoYo announced that Electro reactions will be buffed in a future update. Players have been vocal about Electro's inefficiencies since Genshin Impact released, and miHoYo will finally fix the issue.

What damages electro in Genshin?

Damage. Electro-Charged damage is only affected by the level and Elemental Mastery of the character causing the reaction (and enemy elemental resistance). It ignores the target's defense stat and the attacker's attack stat, and it also cannot deal critical hits.

What was the EM buff Genshin?

Elemental Mastery received a significant buff to its damage scaling. Nable's approximations show that 300 EM now gives up to 208.7% more reaction damage compared to the previous value of 117.5%. This suggests that the EM scaling has effectively been doubled.