You cannot compare one field to another in SOQL, regardless of context. If you want to compare a custom date field to
CreatedDate, you will need a separate checkbox formula field to do the comparison for you, then you can filter on this field being true.
Take a look at the documentation on fieldExpression Syntax (emphasis mine):
fieldName comparisonOperator value
value: A value used to compare with the value in fieldName. You must supply a value whose data type matches the field type of the specified field. You must supply a native value—other field names or calculations are not permitted. If quotes are required (for example, they are not for dates and numbers), use single quotes. Double quotes result in an error.