If that's the case, than why has all these characters broken these fan rules?
People said Ridley was too big, yet they added him.
People said K. Rool was irrelevant, yet they added him.
People said Banjo & Kazooie couldn't be added because they were owned by Microsoft a competitor and said they were irrelevant, yet they added them.
People said we wouldn't likely be getting Nintendo reps in Fighter's Pass 1, yet they added Byleth.
People said Spirits couldn't become playable characters, yet they added Min Min.
People said they would likely never add secondary non Echo unique 3rd party reps, yet they added Sephiroth.
Over and over again, certain character inclusions are constantly breaking fan rules that community treats as official rules. Soon the other rules like "No Assist Trophy promotions" and "No company can double dip in the same Pass" will eventually die as well.