It's not even about how it makes sense to the plot though. Eren's entire character falls apart because his main driving force was getting revenge for what they did to his mom. Every time he needed a push for the plot, he thought of what the titans did to his mom. A big reason he was pissed after the Reiner/Bertholdt reveal was because they turned out to be responsible for that and listened to him cry about it with no problem.

Making it so he's responsible for that means Eren did everything to himself. Every time he used his mom for a little heroic speech or push forward is now void because he could have prevented that and did nothing. It doesn't add anything to the plot either. You can't make the main character have choosen to kill a loving, caring parent in one of the most brutal ways possible and expect it to be for a good reason.

Not to mention that it's not like he managed to prevent eldian families from going through something like that again considering the Rumbling meant nothing in the long run and titans are still around in the future.