Plenty of priests have fucked kids.
Religoius people are often enough the same amount of assholes or more. I have not fought over a city for ages due to some believe.
Something to keep in mind is that religious societies have existed for millennia, whereas societies that are openly non-religious are a relatively recent development, so comparing the two ought to account for a potential lack of historical hindsight on one of the sides.
The parent mentioned specifically religious believes as a tool for good child upbringing.
My counter argument shows, that religious upbringing doesn't necessarily mean a good moral & ethics.
No, I merely pointed out that religious upbringing is explicit about some topics in ways that non-religious one usually aren't.
Your counter argument can be flipped around into "religious upbringing doesn't necessarily mean bad morals & ethics", so in effect it's not really saying anything meaningful.
If you're seeing a factual argument exclusively as some sort of attack on your belief system, then you're missing the point that self-improvements efforts shouldn't be discriminating against an idea solely due to the source of insight.
In other words, if a statement is "you don't talk to your kids about morals as much as [insert religion] people do", it's petty to respond by saying "well the religious group you belong to has people that do poopy pants stuff" (even more so if some atheists also do said poopy pants stuff); it's more productive to instead say "huh, how then could I talk to my kids about morals more often?"
I read it like that as well. I've seen this idea illustrated this way: a kid raised in a religious community gets drilled from an early age about morals as an umbrella abstraction (in the form of allegories from religious texts), so they don't need to be micromanaged about the moral implications of every individual scenario under the sun ("don't run in the supermarket!", "don't push your sister!", "don't yell in the hallway!", etc etc) because they are explicitly exposed to an underlying set of values to govern every scenario.
That's is an obviously religious leaning take (I heard it from a jewish person, though I'm not jewish myself), but I think there's a certain grain of truth in the sense that non-religious people don't have a standardized way of talking to kids about morals as an umbrella abstraction on a weekly basis, in a way that church goers do.