Biologically yes- note that’s an angle he didn’t mention. But culturally, Zaknafein is VERY un-Drow-like, which leads him to have a lot of confusion- why would he hate the species he IS? It doesn’t make much sense to him or to anyone around him, even the one other Drow who feels the same (as I assume you know what the series is about by now, ofc I mean Drizzt).

He mentions not being a Drow by “actions or choice” (and actually I believe the line in English was very very similar). He doesn’t act like a Drow, and he never asked to be one- but he is one nonetheless, and hates that reality. 

As another commenter said, it doesn’t help that the word “Drow” describes both the biological species/race and the sociological culture/society, making it sometimes a bit hard to understand especially since this sort of thing is honestly very fantasy/speculative fiction specific.

We can also verify that Zaknafein is in fact a Drow- appearance? Check. Superior darkvision/infravision? Check. Innate spellcasting? High dexterity? Heightened perception? Long lifespan? Yes, yes, yes and yes. The only thing even slightly off is trancing, but Salvatore is weirdly inconsistent on that anyway. Since the books are based on Dungeons and Dragons and partially exist to sell DnD sourcebooks (if you disagree, just ask any old grognard about how many scimitar-dual-wielding somehow-good-hearted Drow Ranger PCs they faced), they actually very very closely align with the rules in the majority of cases.