We do have inherent designed morality, because morality exists and we know of it because of the fruit of the tree in the knowledge of good and evil. So since morality exists and is real, everyone has a knowledge of it from the beginning.

However, Atheism does like to contravene morality and redesign the moral compass to suit whatever agenda someone would like to push. An example being is the dehumanisation of Jews and people being desensitised to violence to perpetuate the holocaust. Showing opposition brought social and political persecution, all to benefit an authoritarian agenda of militarism and not balming themselves.

Or for a more present and relevant example, foetuses being dehumanised and abortion being normalised and showing any opposition to it may bring social persecution, as to benefit a capitalist agenda and being told “it’s for the good of our freedom” while it actually just relieves the state’s responsibility to care for it’s young and to keep young women in wage slavery.

So yes, Atheists can be moral. But my point is- once you throw God’s solid and unchanging word out of the window, you can warp and “normalise” immoral things and do what you want.