As for the original question:

The Dark Side is the embodiment of all negative emotions, and while sometimes a little negativity is helpful, the Dark Side, by its nature, corrupts its users

So even if they claimed it for non-evil means, commitment makes them evil.

It's not evil in and of itself, per se, but in practice it may as well be

^^ I agree they are not usally good people at all and that Ventress is a better example of a Dark Jedi, also im not biased to Dark jedi im biased towards sith in specfic and mostly Legends continuity as a whole, other than that Im not biased to anything else in Star Wars.

Mace Windu is a great example of someone who wasn't necessarily evil, yet they Tapped into the dark side nonetheless

^They is a he bro first off 💀.

And he isn't even close to being evil he just has a by the books attitude and doesn't trust the man who is responsible for the Empire

If you learned the dark powers but only used them for good, then you would be good. For example Darth Me uses force lightning to provide electricity for remote settlements.

It isn't evil, but it opens the door to unlimited power, which easily corrupts. In Legends, the dark side was definitely more evil, as Sith spirits could possess you, etc.

@Darth Malice24 Your video states that Dark Jedi only think for themselves and don't care for others... That's evil no matter what perspective you look at it

^ Im not gonna keep this going, its heavily off topic at this point and really is a battle of outlooks and in this situation neither of us are open to change the way we see dark jedi so this is a futile argument .

There are canon stories of objects (such as lightsabers) or locations which have dark side energy. These stores show that these things are used to “test” prospective Jedi to see if they can resist the dark.

In other words the dark force can actually influence you to go dark, if it is strong enough and you are weak minded enough. This is an argument in favor of the dark side of the force inherently having an evil attribute.

I see this debate as being very very similar to the “nature” versus “nurture” argument on what makes humans what they are as adults.

In other words there is no clear right or wrong answer. Instead there is some evidence to support both sides.