I think that’s quite reasonable, yes. But I think that it’s accepted that the moral teachings of Jesus were not some sudden insight into the human condition that he brought to the masses. As has been seen, and agreed to by most, the concept of do unto others and non-violence had been around for millennia in different cultures before Jesus took the opportunity to re-emphasise them to his followers. Just as, for example, Gandhi did with his.
So those who follow Jainism or Buddhism or Hinduism have the same rules for moral behaviour as those who follow Christianity. And it’s obvious that a Hindu, for example, would be puzzled by any insistence that his moral behaviour is somehow ordained by someone else’s god.
Let’s not forget that we aren’t discussing ‘Can atheists be moral without God’, but can morality itself exist without the Christian God. So it’s not just a few of us unbelievers who find it an odd question, but millions of people who follow a different belief system would as well.