They did not "take away" Sokka sexism in the Netflix Avatar The last Airbender adaptation!l. They just made it more realistic to what sexism actually looks like in the real world.
In the original cartoon, Sokka's sexism is very one dimensional, a "women can't fight!!" attitude and he immediately gets humbled and learns he's wrong. It's a pretty simple depiction of misogyny, but it's good because after all, ATLA is a show for kids (that doesn't mean you can't enjoy it as an adult) but having a simple depiction of sexism = bad is perfect for what the show is.
However, it's very clear the Netflix adaptation is a bit more mature in tone and takes its themes a bit more serious. Its still "all ages" but I would not show it to young kids with the whole burning people alive stuff. So because it takes a more serious approach to the story, it also does so with Sokka's sexism arc! Instead of just being like "women can't fight!" he assumes by virtue of being a male who was handed a club, he is the equal of Suki and the Kyoshi warriors. He literally says this, that he thinks they are practically the same. Suki rightfully gets pissed about it! She has trained her entire life as an elite warrior. Him and her are NOT the same. And in this version, Sokka again, gets immediately humbled and learns he was wrong.
This version of sexism is waaaaay more accurate to the sexism we see around in modern society today though. We don't really see a ton of people saying women can't play sports, but that there's a lot of men who think just because they played a sport in highschool, they could match up equally with (or even beat!) a professional woman athlete. All just because they are a guy!!! And this is the sexism that Sokka exhibits, and is refuted! It's a GOOD change because it's showing sexism (and how wrong it is) in the subtle way it is more likely to show up as in the real world!