system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] If the Dark Side, as Yoda said, is quicker and easier, then how is it not more powerful? It's so much quicker an easier that a 60 year old Sith defeated an 800+ year old Master Jedi? Doesn't that make it more powerful by virtue of its quickness?

Also, Yoda was known or being exceptionally strong with the force naturally, even without his 800+ years of experience.
gpt
Legends, but one quick example - a lone mediocre Jedi who happened to be in the right place and the right time was able to single-handedly hold off an entire army of extragalactic invaders and brought down the entire building that Yoda and Palpatine had dueled in. Ganner Rhysode went from being a brash, aggressive, and overconfident Jedi to a god of the Yuuzhan Vong. How? By finding within himself, in one crucial moment, the perfect state of being that the Jedi preached and dedicated their entire lives to discovering.

The ideal of the Jedi (which the Order of Yoda's time arguably fell far short of) is that they devote themselves to the will of the Force entirely, such that the Force can act through them - the Force using a Jedi to accomplish a task, rather than the other way around. In such a state of oneness with the Force, the entire concept of "more powerful" is irrelevant; the Jedi becomes merely a conduit for the cosmic power that surrounds and binds all life in the universe. 

No Sith could ever hope to match such an event, as they would be fighting against the very power they are drawing from. Not the person, not the Jedi, but fighting against the Force itself made manifest.