It's overrated because it gives up its ability to hit fairies and moltres a lot of the time, and I don't find it nearly as powerful or overwhelming as many others do. That's my opinion. I just do not see it as powerful as other players may, which is why I consider it overrated. This is an opinion. I am not pushing the idea of it being objective. People can disagree with you and be correct.Primarina dies to +3 ID and doesn’t OHKO. Moon has to exhaust Tera and loses the 1v1 still if the Zama clicks Tera. Gambit doesn’t even always beat Zama unless it clicks SD first and it is Tera Blaat. Hex Pult loses hard to Fire and can lose to Dark despite hitting, which are second and third most common Tera types on it. Moltres doesn’t beat Rest consistently and at best can just Roar it out. Gliscor loses 1v1 to Rest unless Tera Ghost. TWave Ghold and Zapdos, which can still lose depending on Tera, are the only answers there.
Above all, Rest Zama is just insanely good into offense. It’s hardly even just a win condition. It’s a check to a substantial portion of the tier. It’s a gameflow controller. It’s able to last longer than virtually anything on these paced teams. And it’s able to be an initial swap into strong Pokemon like Kingambit, Wellspring, Tusk, etc.
Sometimes it functions as a win condition despite all of this depending on the trajectory of the game, but calling it overrated is just silly.
Also, no. All the answers I listed either 2KO it or status it except for Deoxys-Speed having a hard time switching in. Your opinion is not objective, people can disagree without there being a clear right and wrong.