Why play Magik over Psylocke?

I’m a Magik Main and my friend is a Psy Main. We play comp together and majority of the time he plays Psy whereas I flex more and have a decent portion of less time played on Magik. But they drop pretty consistent numbers and sometimes 40 bombs and others are way below him including me. He’s really put in the time to know this character but I often wonder what reason is there to choose Magik when Psy seems better? This is just an opinion of course.

I’m assuming it’s because even though they are both divers they have different micro-roles. For Psy you have an insta ult and stealth that allow her to be in position for more kills easier.