Because, as a descendant of Adam, you are born with a sin nature that puts you at enmity with God’ righteous nature. The commandments you seek to toss about as ‘doable’ are a short course definition of God’s nature ... God is not a liar, therefor he cannot lie. You on the other hand, bacuse you were bron with a sin nature, can lie ... and hold yourself righteous in your pride. If you were born with God’s nature, as Jesus was, you can be sinless. ANd that’s why He died for you and me, because we could not receive a sinless nature on our own.
Well that is all and good for us descendants but Adam was born without a sin nature so was he prior to his sin and would he had been had he not sinned been sinless, holy and righteous?