First off, he was a racist bigot in a time when that was contrary to the general perception, which is a good deal different than being one in a time when everyone is and it's an utter societal norm

Second off, take out the racist bigotry (that's a big, big thing to take out, since we're talking about a level of racist bigotry where he was laughably supporting the torture and death of Muggles and Muggleborns at a couple points ex. Goblet of Fire post-World-Cup) and take out most of what could reasonably be construed as "normal" in the line of his schoolboy rivalry with Harry (which isn't great) and he still:

--says Harry's dead parents suck(ed) just because

--makes fun of impoverished people for being impoverished

--gets a rise out of causing others distress

--tosses curses at folks at random from time to time for his own amusement

--treats supposed "friends" like inferior servants and condescends to them incessantly

--lies to the press to make people he doesn't like look worse

--abuses his prefect / Inquisitorial Squad status for personal gain or gain for his allies, and for fun

--knows full well that his father is a murderous torturous ass and actively supports his murderous torturous activities and regrets his father's failure to deliver Harry to his death in OotP and then plainly wishes Harry death to his face

--tries to use Crucio on Harry in a completely pointless scuffle

--actively conspires to commit murder and nearly commits several accidental ones in his wanton abandon to do the job (can't go through with it in the moment itself, which obviously helps his case a great deal, but he was still very dedicated to the idea of murder for personal gain until he realized he couldn't stomach it, which is pretty freaking terrible--this is around the time that he starts becoming at least a marginally better person, he is not already a good person simply for not having the stomach for murder, there are loads of bad people who are not murderers), threatening and manipulating all manner of folk (including his own supposed "friends") to achieve this goal

Draco is a bad person for most of his developing life. This is not ambiguous and it never was. It takes an enormous upheaval that shocks Draco to his core to even give rise to the possibility of him becoming a better human being.

Maybe he did have some positive actions at some point off-screen. Doesn't seem like it, based on what we see of Draco when he doesn't realize Harry is there--again, it's made very clear in the books that Draco is a pretty one-dimensional kind of guy up until confronted with the situation in HBP--but maybe that happened. Great. That doesn't magically make him a good person or even morally gray. If you do the kind of things Draco does, if you think the way he thinks for most of those early books, you're a bad person and the occasional act of kindness doesn't make you not-a-bad-person.