>>52848525There are some downsides to tera like losing both your types. You still keep stab for those types but you lose your defensive bonuses.
for example: Cinderace has acrobatics, iron head, pyro ball, and high jump kick.
Your charizard is fire/flying so you resist everything but acrobatics so 90% of the time that's the move they will use. If you tera flying for a boost to you hurricane attacks, you lose your fire defensive typing.
so now cinderace's rion head and pyroball do full damage. pyro ball can burn you now since you're not a fire type and iron head, while weaker, can make you flinch which is really bad.
For support pokemon, it might be after to just stay not tera'd to keep their good defenses but for charizard and other attacker types, just tera.