unfortunately it's not that simple, especially as long as the original behavior is still in there and ... successfully defending the originality of the reimple

unfortunately it's not that simple, especially as long as the original behavior is still in there and ... successfully defending the originality of the reimplementation as a standalone work would be a risky and costly legal endeavor (even though the standards for originality - "is it transformative enough?" was more lenient when OpenTTD was made than it's today)