Eren could’ve used the Attack Titan’s powers to save his mom from dying but instead chose to use it to bully his dad.
Wouldn't saving his mom alter the course of the story so drastically that Lynar/Burrito/Annie would end up succeeding in their mission? Eren feels the weight of his actions, sure, but he stays pragmatic enough to know that saving his mommerino would cross a line of selfishness that would result in many more 'loved ones' deaths.
Also, Eren's resignation unto 'muh fate' is pretty k-k-k-k-kino tbh. Other shounen protags would be all like "we can change fate through the power of dattebayo!"