Why not when God himself in Gen 3 says that we have the same moral sense as he does. They have become as Gods in the knowing of good and evil.
You also forget that most theists have judged their God to be good by their standards. Scriptures even tell us to judge.
1 Thessalonians 5:21 Test all things; hold fast what is good.
The bible seem to think we are able. Why don't you?
Further, scriptures say we should all strive to gain a Christ mind and take the judgement seat from God.
Matthew 6:22 The light of the body is the eye: if therefore thine eye be single, thy whole body shall be full of light.
John 14:23 Jesus answered and said unto him, If a man love me, he will keep my words: and my Father will love him, and we will come unto him, and make our abode with him.
Romans 8:29 For whom he did foreknow, he also did predestinate to be conformed to the image of his Son, that he might be the firstborn among many brethren.
Some of us will do that work and step up. Others will not do the work and just continue to follow lying priests, preachers and imams.
I am a God WIP. If you cannot say that and will not emulate Jesus then keep being an inferior Christian, if you are a Christian, as compared to Gnostic Christian.
John Lennon was correct when he said that the only good Christians were Gnostic Christians.
That reason is why Christians decimated us with their Inquisitions the moment they could.
Both Christianity and Islam have basically developed into intolerant, homophobic and misogynous religions. Both religions have grown themselves by the sword instead of good deeds and continue with their immoral ways in spite of secular law showing them the moral ways.
Jesus said we would know his people by their works and deeds. That means Jesus would not recognize Christians and Muslims as his people, and neither do I. Jesus would call Christianity and Islam abominations.
Gnostic Christians did in the past, and I am proudly continuing that tradition and honest irrefutable evaluation based on morality.