No, it's not. First off, I would like to point out that the person in no shape or form wished harm upon us. That alone, in my opinion, should be grounds for punishment. I do not take that kind of behavior lightly. Nothing one can say or do will make me refrain from filing a report against them.
Second, it's not because they said "sorry", it's because in my prospective, they actually meant it.
We all have off days/games where we say or do something that is in the wrong. We are human after all.
From my personal history, I've had games where I had to quit due to something unexpected coming up; ex. Cousin getting in a car wreck and me having to pick him up, or my GF at the time ordering food in my name so I have to grab it, or even something as simple as having someone come over unexpectedly. I've told my team and also the enemy team that they can all report me for AFK if they'd like. And not once have I been reported for going AFK. Why? Because they understand. Much like here, I understand that things can get irritable, even frustrating. I understand from personal experience that one can take it out on a loved one, inanimate object or even what they are currently occupied with. I understand it all.
The fact that they didn't mean any harm to come from their mouth and that they gave an honest, heartfelt apology (without asking to not be reported, might I add), made me decide not to report them.
We are all human, we all make mistakes.
We can make this more clear by putting it in a real life scenario. One that we all have experienced. Someone has done you wrong and you are upset with them, but later they come back and apologize. If you felt the apology was sincere enough, you (usually) accept their apology.
That's what happened in this case for me.
