Idk about y’all, I’m 70% confident Luigi is the perp. I think that (assuming Luigi is the perp) he wanted to either:

[1] Eventually get caught, but merely delayed it to see reactions on social media, so that no innocent person becomes a scapegoat, and also for the purposes of getting more media coverage via the “manhunt” so his Manifesto/reasons for doind it is more widely spread. (I mean, it did last a few days on the news, so that was a lot of media coverage)

[2] He had more targets to “depose” but got caught before being able to do so.