I've seen some anecdotes about Stellar Tera in raids feeling weaker than expected despite the universal boost, potentially because Stellar is not the actual type that matches your move, so you get the weaker off-type tera damage against shields instead of true STAB tera doing about double the amount.
"I entered a Tera Raid against a Fairy Lycanroc using my Stellar Empoleon, and when I Terastalized and used Flash Cannon, it seemed to do only the 30% damage of a regular Terastal move against the shield, rather than the 70% damage a matching Terastal move does."
"I entered a Tera Raid against a Fairy Lycanroc using my Stellar Empoleon, and when I Terastalized and used Flash Cannon, it seemed to do only the 30% damage of a regular Terastal move against the shield, rather than the 70% damage a matching Terastal move does."





