Lots of rambling ahead. This is a stream of consciousness and is not edited
I like to remind people that Kurogiri almost killed All Might because it's very interesting to me that like... MHA is fascinating in how it definitely exposes people's ideas of justice through its discussion of it. I don't see that often, but I find that it's a very good read on someone's personal compass. Unfortunately the narrative did allow for death penalty supporters and people who are particularly bloodthirsty about criminals to be somewhat validated by the text. You see it how people talk about Toga, Shigaraki, Dabi etc and how they died in the series
But. Like. People do not often treat Kurogiri in the same way. Often his death is seen as bullshit even by the same people who think Shigaraki got what he deserved. That, or they excuse it by bringing up "he was dying anyway" or "he's already dead" or "he's being put out of his misery", the first being a watsonian excuse for a doylist criticism, the second being a factual misreading of the story, and the third being a common ableist talking point that doesn't deserve the time of day
They don't bring up that he participated in the attack on UA, helped with Bakugo's kidnapping, helped AFO steal many people's quirks, and an implied but untold many many many other crimes committed under AFO's behest. Remember when he spread the 2Togas everywhere which unintentionally led to the deaths of all of the LOV? I do! A lot of people don't, or are willing to give him the benefit of the doubt. Contrast with Shigaraki who is seen as irredeemable despite the majority of his actions being influenced by AFO literally possessing him, or by AFO having completely taken over his body. Shigaraki as a lone person likely did not do much worse than Kurogiri, and was under the same kind of grooming and brainwashing, had a heroic background and is just as tragic of a victim of kidnapping/abuse, but despite all that he is treated with a sense of revulsion
That's not to say that there aren't people who see Kurogiri as just a criminal that deserved to die, but it's not the common rhetoric. It's not just that his death was stupid, but there is a more general sense that Shirakumo should not have died anyway. Why is that? I personally believe it's because Shigaraki didn't have an Aizawa. People rooted more for Shirakumo's return and sympathized with him more because he's Aizawa's friend, and is therefore willing to overlook the sheer level of damage that he personally caused in the final war. I don't think it's the mental instability, because like... so was Dabi, and Toga, and Shigaraki especially. No, I think it's because Kurogiri has a friend, and we all like that friend, and that friend knows who he was and believes in him
Dabi is rougher around the edges as he always displayed signs of continuing the cycle of abuse at a young age. He has his brother, but they never really knew each other, and Endeavor is not a character that people commonly root for lol. Therefore Dabi's death is seen more as an inevitable tragedy. Ochako knows Toga but she also... kinda doesn't. She doesn't really understand Toga until it's too late. The story is also wrapped up in a shakily written heterosexual romance that an average viewer might find to be cheap, even if on a subconscious level. Shoji and Spinner was pretty much a failed attempt at creating a connection between a hero and villain. Shigaraki and Deku had a connection similar to togachako (the hero tries to understand the villain to save them, but they don't until it's too late) but it's even more distant than them, on top of their connection being wrapped up in the themes of what justice and saving people means
Of course, like, all of these things does not excuse the punitive justice bloodlust, just explains why an average viewer likely feels less sympathy for these deaths, or is more likely to try and find some explanation, or find it to be a fitting ending. Meanwhile, Shirakumo's second death was just incredibly stupid, a true tragedy of writing quality, there is not much excuse to be made for it. There are ways that he could've died and would have created a stronger argument for it being a fitting tragic ending (I've talked about a couple of these possibilities in the past). Combine that with the fact that he had a friend that we care about, and the friend cares a lot about him, and... you get an audience that is more okay with overlooking his very recent crimes and damage within the story lol
I also like to bring up that Shigaraki was also killed by AFO. Remember that? A lot of people understandably missed it, but Shigaraki was not killed by Deku. It looked like he was, hence the murderer allegations and the guilt, but Shigaraki was already dead by AFO's hand when he helped deal the final blow to AFO's vestige. Deku failed to save him in time, and then "killed to save". Shigaraki, in essence, helped destroy his own possessed body to defeat AFO. Personally that completely changes the narrative on Shigaraki into a tragedy rather than some upholding of punitive justice. Unfortunately it wasn't... written very coherently at all. Themes and such... Tragedies and such. All of the LOVs deaths are tragedies more than a support of punitive justice, but unfortunately basically the entire fandom took it as validation for that punitive ideology.. because it wasn't written that well.........