The then South Korean opposition wasn't in power at the time, and yet they spearheaded the impeachment and eventual arrest and prosecution of their previous wannabe dictator, who insurrected a coup to prevent him being impeached. Brazil got lucky that their Brazilian Supreme Court was found to be corrupt and aligned with the previous authoritarian Bolsonaro, which led to the replacement of the judges. The new judges along with the other branches of government and opposition prosecuted Bolsonaro.

Brazil and SK opposition prosecuted their dictators to the fullest authority of their laws. The US? They're spineless. Even after Trump's insurrection and after Biden took power, all the US branches failed to prosecute Trump and the Democrats did not hold him accountable. He regained power as a result.

The truth isn't about who holds the seats, it's whether or not politicians and bureaucrats have the political will. The American population have been conditioned to stick to "decorum", even though the opponent is playing dirty and not playing by the rules. The difference is that Brazil and South Korea experienced dictatorship so they know to call a spade-- a spade. The US, hasn't experienced dictatorship, and to be blunt, after exporting to other nations; and couldn't tell that it's dictatorship after throwing it and returned to the hand that threw.