Pokemon s unfortunately a linear game but I judge things like overpoweredness and brokenness on how it affects the card pool and what it forces a player to do. Feelings have no place in that system. Safeguard is an Ability that the game needs but Carbink doesn't have an attack that prevents play. It's Ability can be turned off via Silent Lab, meaning you don't have to play a Supporter. I also don't want to entertain what ifs because Carbink doesn't do anything like that. Safe Guard is a better Ability than what Giratina-EX has but you look at everything as a whole. Carbink isn't a 170 HP Basic with very disruptive attacks that has synergy with four decks while being a Bench sitter.
Difference here is Giratina-EX forces you to play a Hex Maniac and or Pokemon Ranger to do something in that turn, taking away another option from the opponent. Those players must draw like gods if they can see a Hex Maniac when they need it.
Your reply is drenched in bias, but I'll attempt to explain this one last time.
Basis for my opinion:
Giratina is not overpowered, because it's strengths only cater to specific niches.
As such, it can only ever be a supporting attacker.
A lot of decks have supporting attackers, but most do not use Giratina.
This is because it needs DDE to keep up, and the natural state of the meta allows players to play around the card.
Hex Maniac is not run
because of Giratina.
Hex Maniac is run because it shuts off a lot of cards in the meta; same reason why people are running Wobb and Silent Lab.
Giratina being affected by this is another reason why the card is good, not the
only reason.
Giratina as an Attacker:
Total energy cost = 4
Total attachments = 2-3
Potential damage = 100-130 (with Band)
Potential HP = 170-210 (with FFB)
These statistics are all average, or below average.
The effect of the attack is what makes the attack "good."
If you take away the effect, or take away DDE, the attack is no longer good.
The damage is outpaced by other Pokemon already (Lurantis, Volcanion, etc.)
These Pokemon also do not use special energy, and as such, will be able to outpace it even with the effect.
Giratina as a Wall:
Giratina is not effected by...
Megas
EXs
Basics
Evolution Pokemon
GXs
Being able to wall something is a "good" ability.
However, Giratina's walling is very situational.
and, unfortunately... Every competitively viable Mega will OHKO it when it's ability is off.
Mega Rayquaza, potential damage = 30-240
Mega Mewtwo, potential damage = 70+ (with Giratina's 4 energy cost, it will be OHKOd at it's base HP)
Mega Gardevoir, potential damage = 110-190x2 (Weakness)
Because of this, Giratina is not a reliable wall, and is mostly just used to hold DDEs.
It's attack and ability are what make it (arguably) the best dragon to do so.
You don't run Giratina to wall Megas, you run Giratina because it's a "good" card that can hold DDEs to boost your attack.
This is why we don't see solo-dragon decks.
They all need DDE, and most of them cannot keep up with opposing attackers as it is.
Cards like Giratina and Salamence are strong
because of the meta.
They do well in very specific situations,
and are able to hold DDE.
With these things combined, people have deemed them viable.
While they may see play in decks without DDE (Salamence in Volcanion), those are usually considered worse and/or less consistent variants.
I hope my post has allowed you to see the flaws of Giratina, and understand why it is a balanced card.
If not, then I have unfortunately wasted my time.
Either way, I feel like I cannot explain this with anymore clarity; so this will be my last statement on the matter~