Question for those on the Council or to whom it may concern, why is Stellar Terastallization being considered separate from Terastallization when the game considers the former a part of the latter mechanic?
And as such, if Stellar Tera is banned, why is this not a Complex Ban that opens up the can of worms that banning individual Tera types is?
Is this seriously being considered a separate mechanic from Tera or are people just speculating?
This doesn't address the fact that Gigantimax forms were banned alongside Dynamax due to being the same mechanic, while discussions (not from the Council in fairness, but from a large portion of the community) seem to want Stellar Tera to be treated as its own thing as to not endanger the mechanic as a whole.
How good it is aside, shouldn't precedence point towards the Stellar Tera type being just one of the many Tera types the mechanic of Terastallization allows you to access?
I love tiering policy dilemmas so I think I could address this.
Since the 18 types are some of the most fundamental mechanics of Pokémon, a lot of people generally view the type-based mechanics associated with them (Hidden Power, Gems, Z-Moves, type-boosting items, Tera) as equal and and a singular element even though not all types are created equally in strengths and weaknesses. In other words, you can't ban Normal Gem or Hidden Power Fire alone without banning all Gems or all Hidden Powers since they are seen as one element, not eighteen. However some may argue that banning a specific type of a typed-based mechanic isn't actually too "complex" of a ban. For example, if Flying Gem Acrobatics is overpowered, then there may be a case for Flying Gem (or Acrobatics) to be banned without banning all Gems. So far there is no official verdict on type-based mechanics being considered as one element or eighteen different elements, although the Gem ban in BW may provide some insight?
Regardless if type-based mechanics are seen as singular or eighteen, if a mechanic differs in more than just typing, then it should be viewed as a separate entity. Think Legend Plate or Expert Belt vs the normal Plates/type-boosting items. If you can tier the Legend Plate or Expert Belt separate from the normal plates, then you can tier the Stellar type separate from normal Terastallziton. This is also why Max Moves should be treated differently than Z-Moves or Hidden Power in hacked metagames. Max Moves aren't just the same mechanic repackaged in different types due to their different secondary effects. I think a case can be made for Gigantamax and Dynamax to be treated as separate, but since both are extremely overpowered, it doesn't matter whether they are treated as one or two; they are still staying banned.
The only reason why the Stellar type is being combined with standard Tera is because it is the only one outlier out of the whole mechanic. Imagine a scenario where the item mechanic only consists of Plates and Expert Belt. If you think it is ridiculous to ban the entire item slot because Expert Belt is overpowered, the same logic should apply to Tera. If there are 10 additional kinds of Terastallization, then then it would be viewed more similarly to items or Z-Moves.
The Stellar type exists outside the type chart since it only works when Terastallized and you don't even change your defensive interactions, so it should be viewed as its own mechanic.