I sort of agree with it. It must add some serious brownie points!
Well, here’s my take on it.
A gangster, who murders people, deals drugs, and runs a prostitution ring-- and who has never set foot in Church in 30 years-- runs into a burning building to save is mother.
That is a virtuous thing to do, but also a selfish thing on his part, it’s his mother after all (and if it were a stranger he would not have done so).
This does not reconcile him to God and the Church. This does not forgive his mortal sin (which only God knows if all of his criminal behavior meets the three criteria for mortal sin. We know it meets grave matter, but only God can judge full knowledge and free will)
And, one who dies in mortal sin cannot enter Heaven. So, if he is in mortal sin he will not go to heaven just because he did a good deed, no matter how brave, rash, or heroic.
Only a perfect act of contrition in his dieing moments could alter the course.
If he is in mortal sin, this does not forgive his sin. If he is
not in mortal sin, then he was going to Heaven anyway and this did not change that.
Now death for the
Faith– martyrdom-- that could indeed reconcile him with the Church and forgive his mortal sin.