I just recently watched both of these series again for like the 49th time and I think it's time y'all realize there's nothing to compare skdks they're actually polar opposites. But we'll get to that.
First reason is their journeys within themselves are completely different and as I said polar opposites.
Aang when he started off he had a sense of self spiritually but needed to find his power physically. He's always known himself and his goals and who he wanted to be but he struggled with the fear of his power and what he could do to other people.
Korra on the other hand knew her abilities and powers at a young age. She was a prodigy and she knew it. But when it came to Korra she needed to learn her sense of self. Her journey humbled her and she was able to find her spiritual side.
Morality : From a younger age Korra and Aang were raised COMPLETELY different. Aang was a monk who didn't believe in harming any living being whereas Korra was so used to fighting to solve everything. So how they handle things ofc will be different no doubt.
Villains : In Aang's series it was building up to one goal and that was to take out the fire Lord. While some people came along the way Ozai was always the goal when it came to the entirety of all seasons.
Korra on the other hand every season had to build herself up to beat the villain by the end of each. On top of that almost all if not all of her villains were special benders so she herself had to unlock abilities to defeat them.
In conclusion there's really no comparison when it comes to them. They're completely different people and that's okay. Wanting them to be the same is actually pretty unoriginal so find something else to be upset about lmao.