I almost disagreed because I don't blame Maxi at all for her shortsightedness in wanting to be useful, but I ultimately agree with your point because I do think people can overlook that quality of her character, which is obviously fully intended by the author to be a contrast to Riftan's desire to protect her, and criticize that purposefully equal flaw in Riftan's character to the extreme. I'm not like super fond of him, but for the time period he comes out of he's fine, and I think he is a perfectly serviceable character for this narrative.

I don't totally hate Riftan and think some of the criticism he gets is not completely justified. Let me be clear, he's not an upstanding guy or someone I would like in real life, and I do think that he has issues to work through alone. However, we need to acknowledge that Riftan has been harsh on Maxi to ensure her safety as he's supposed to be the knight that protects people, and he's especially supposed to protect his wife. Maxi then decides to learn magic, that's cool and all, good for her. Then she decides she wants to join a war while having little experience with magic and with being on a campaign. Like I get she wants to protect Riftan, but compared to him she still needed time. The best bet would be for her to stay back and train, then she would gain that experience to be the protector. Like I also didn't like the story direction with her forcing her way into the campaign, because obviously that would only hurt her and not actually teach her much.
Spoiler warning begins!
I know Maxi later leaves to train and people say Riftan sucks for not agreeing because she wants to protect him, but they get mad at the fact that Riftan wants to protect Maxi in his own way too. Like Riftan is obsessed with Maxi but he also wants to give her a better life meanwhile Maxi runs into danger constantly unprepared because she wants to be useful and in doing so only makes it harder to protect her - because lord knows people would complain if Riftan stopped protecting her as well.
Spoiler END!
Riftan is not my favorite character because he is a jerk a lot, but honestly Maxi deserves more criticism on this one issue. Just because she wants to help and be useful due to her trauma doesn't mean she hasn't made shortsighted decision for her own peace of mind the same way Riftan has.