There’s no way of knowing how many worlds Draenei have tried to settle or what sort of life was already there and what their fates were.

No matter what, though, you can’t deny the fact that Draenei came to Draenor knowing that the Legion was hunting them and that their presence jeopardized the lives of all other inhabitants.

Yes, all worlds are in danger of the Legion sweeping through like a fiery green juggernaut of dicks but the Draenei’s presence is basically a confirmed death sentence that the native’s have no voice to reject. The Draenei could have welcomed other races onto their ships as their planets burned that simply died out because of life span differences, but it doesn’t erase the fact that the reason they offered in the first place is because their very presence caused it.

That doesn’t mean Draenei deserved what happened to them.

Personally, I love the idea of the Draenei being a dystopian oligarchy that not so subtly holds themselves above others. There are going to be vocal opponents to this that preach doing this goes against the Naaru’s teachings and the Light because all life is sacred. There will be those who see the Draenei race as the chosen ones who have to put themselves above others because they must survive to fight another day and destroy the Legion.

Imagine all the scientists who tried to push for perfecting spaceship technology to make it just as comfortable as a planet while others were more concerned with trying to keep the damn things floating. Imagine the politics and internal schisms that are centuries old. Imagine all the Draenei who stare behind on planets as protest and were wiped from all memory crystals. Imagine the normal citizen Draenei who are more concerned with living their day to day lives and making it another year or the parents that dream of their children having a planet to call their own no matter the cost. Imagine the Draenei who have just never even considered the salted ground they’ve left behind.

Idk man, it’s almost like no race is just one thing.

I wouldn’t call what they did exactly imperialism or colonialism but at it’s core it really isn’t much better.

You say this like it wasn’t going to happen anyway, here’s an excerpt from the new Illidan novel:

[Vandel] became aware that all around him in that void were millions upon millions of worlds, teeming with life and glittering with promise.
He focused on one and saw a golden land, bright with sunshine where a care free people harvested. Then he saw a portal tear open in the fabric of reality. Through that rent poured the unstoppable forces of the Burning Legion, invincible armies of demons, bent only on destruction and slaughter.
All of this had happened many years ago. Long before the Legion had ever reached Azeroth it had smashed its way across countless worlds, destroying everything in its path. Its sole relentless purpose was to kill.
He saw gigantic ruins, toppled buildings that had once reached the sky, lakes of glass where proud cities had once stood. He saw the lights of life in the universe wiking slowly out until only a few remained.
He never doubted the truth of what he saw. The Burning legion left behind a trail of smoldering worlds in its wake.

The danger from the Burning Legion isn’t just some abstract concept, its a real and present thing that endangers every single living thing in the Warcraft universe. While Draenor might have received undue attention from the higher ups in the Legion due to the presence of the Draenei, there’s no mistake that when the Legion encountered it, they would have suffered the same fate without them.

This sort of description happens later on in the novel as well, to Illidan himself:

On and on his spirit flashed, passing through dead world after dead world, monuments to the eternal malice of the Burning Legion. Everywhere lay ruin. This would be the fate of Azeroth and Outland and the few remaining living worlds once the Burning Legion attacked. 

The Burning Legion is omnicidal in the truest sense of the word. Yes they were hunting the Draenei, but they’re also hunting everything else at the same time. Just because you don’t have the Draenei visit does not mean you’re safe from the Burning Legion. Simply attracting their notice is a confirmed death sentence.