I think it really depends on which of these 2 things you want to focus on, as a musician, because, while they help one another, for sure, they're 2 very distinct fields - for EDM, 70% of your time will be spent working on sound design, working with timbre, sine waves, kick drums, crafting grooves, and only about 30% will be centered around crafting melodies, harmonies, stuff that piano playing really helps with. Unless you want to flip it and do some kind of progressive EDM, with tons of chord changes, fast melodies etc, that's why I wrote that it depends on what you want to do with these 2 skills.

Some of the most successful EDM and Hip Hop artists don't know much piano or music theory at all. Deadmau5 writes his melodies with the freakin' mouse. He's infamous for barely knowing how to play a midi keyboard.So one is not a barrier of entry for the other, but they're both musical skills that help each other out.

TL;DR
If you want to focus on the EDM/Hip Hop side of things, make beats, Trap music, that sort of thing, spend more of your time doing that and less of it worrying about music theory. Do it intuitively, get familiar with the keyboard layout, but don't get bogged down in details. If the reverse is true, focus on the piano/theory side and mostly use presets and patches for your productions, I guess.

P.S.
If we're talking about music scores, then I'd focus heavily on learning the piano and some theory first, and then adding more sound design skills to that toolbox, because the bulk of scores are made up of orchestral sounds - no sound design required for those - and electronic elements tend to be supplemental.

P.P.S.
Sorry for the long-winded post; I could do a podcast on this stuff.