What do masteries (not just keystones) actually provide outside of balance issues?
Runes are a much more balanced system. Small boosts that you can tweak to fit your playstyle, but don't really push anything or anyone over the edge.
Yeah, they're boring stat-boosts, but they don't ruin the game and haven't really ever upset balance in any way.
Masteries, meanwhile, have always caused balance issues in League, even before Riot was over-tuning them, but ESPECIALLY during seasons 6 and 7.
#Can we just remove masteries at this point?
I honestly haven't seen them add anything to the game outside of issues in the past 5 seasons.
Try to argue otherwise.