Pokémon Anime Some of Ash's Officially Trained/Bonded Pokémon Not in the To Be a Pokémon Master Sub-Season

As of the end of The Rainbow and the Pokémon Master!, the To Be a Pokémon Master sub-season finale, I knew that some of Ash's current and former officially Trained and/or Bonded Pokémon that didn't physically appear in the To Be a Pokémon Master sub-season included:

1. Butterfree
2. Primeape
3. Noctowl
4. Larvitar
5. Torkoal
6. Ambipom
7. Gliscor
8. Gible
9. Greninja (even though it appeared only in a flashback as a Frogadier)
10. Goodra (even though it appeared only in a flashback as a Goomy)
11. Lycanroc
12. Nebby, nickname of Solgaleo
13. Naganadel
    
14. Melmetal
15. Lucario (even though it appeared only in a group photo)
16. Dracovish (even though it appeared only in a group photo)

Now I wonder why you think some of Ash's Pokémon didn't physically appear in the To Be a Pokémon Master sub-season as of the end of its finale?