It’s also far from the worst thing red fascists have done so it’s just so weird how hard people focus on it.

That's the point. There's lots of things Stalin and Mao did wrong, but when reformers like Khrushchev or Deng came along, there were some in the West who viewed them as more moderate and sympathetic, and supported deescalation.

Trots, who were some of the most militant and aggressive cold warriors, wanted to play prevent this, so they came up with the term tankie, to imply that anyone who took that position was no different from someone who blindly supported everything done by Stalin, and then Mao.

This is why people are so hyper-focused, even now, on minor events like Tienanmen or Hungary, which pale in comparison to the bad things Stalin and Mao did, and are roughly as far back in the past. Because the real point of the insult is not to attack people who actually defend everything done by someone with a red flag, but to attack people who defend any single thing done by someone with a red flag.

This, in turn, raises the question of whether Khrushchev had the right approach at all with trying to deescalate with the West and change some of Stalin's practices, since even relatively progressive Westerners hated him just as much for it. In reality, there's literally nothing you can do to appease Westerners, y'all hate China for having billionaires and you hated before when it didn't have billionaires; you hated Russia when it was led by Stalin, you hated it when it was led by Kruschev, you were briefly ok with it when it surrendered to plundering, but even then, now you're back to hating it. AES states are clearly better off just accepting that Western "leftists" will always hate them regardless of what they do or don't do.

I seem to have conflated multiple things there - that is a common test that is often used to determine if someone is to be labeled as a "tankie", but yes is not its actual definition.