Performance at those levels is far more important than class selection, but most people would rather blame the class and not how poorly they play it.
In short, play whatever you want since you aren’t pushing world firsts or 25+ keys.
So much this…
My 2 cents on this topic is basically what other said… Arcane for fun and Fire for high end raiding and mythics.
I don’t raid hardly at all anymore so I play arcane for fun and the lore/theme…