That means they're both QTE based?
Proportions matter.
Executing the action, dodging and parrying, and shooting ranged weapons all happen in real time.
It works really well in practice, combining both strategic and twitch gameplay.
Personally, I killed Simon on my second try by rebuilding my party to intentionally die to his attacks, proc some key Luminas and trigger the start of a high damage combo. The game rewards creative builds and lateral thinking.