The Constitution does not say any such thing. That is all *OPINION* put forth by lawyers who likely never considered the current predicament where nobody knows if Biden was even aware that things were being signed in his name.
As Mike Johnson demonstrated, Biden was completely unaware that he had suspended LNG exports. He said "I didn't do that."
Someone on his staff sure did.
In 2005, President George W. Bush sought a DOJ opinion on whether the autopen could be used to sign bills into law. The DOJ concluded it was constitutional, but Bush never used it for this purpose.