Trinity not working on split arrow or rain of arrows

So yesterday when doing a practice run of the campaign decided to try out some skills i havent used in a while and stumbled into finding out trinity does not work on skills that do not have a elemental tag.

So the game lets you support the skills even says they work in the support help popup window but the gems will never gain resonance no matter what you do for elemental damage. I tried this out on multiple characters with split arrow and rain of arrows with different elemental dmg layouts and the gems just will not gain resonance.

Was physical your highest damage? You wont gain resonance if thats the case.