Opinions are opinions, but I'm gonna disagree with this characterization. I was there for the stream she vented in and she didn't mention a name or make any sort of insult. The comment was entirely about how she was still treated as the devil on the JP side so many months after February when dramafags had largely moved on from other controversial figures.
This was followed by a bunch of nothing among both JP and EN fans, with people still assuming they were on good terms in both Mike's and Delu's fanbases (just look at the Coco, Rushia, Aloe Akatsuki fanart people were posting that didn't age well). Shit didn't go down until Delu released her fanbox post directly naming Mike and it started getting posted on imageboards and reddit. Nobody was talking about it and there's no way it could have been more than a handful of schizos DMing Delu for it to have been so quiet in the sizeable period between the stream in question and the fanbox update. There was no public image at risk and no pressing need for the two of them to even be on speaking terms if they just plain didn't like each other after the incident.
I don't think it's fair to say Mike started shit with Delutaya, because it was ultimately random assholes on the internet instigating an interpersonal conflict between the two of them via DM telephone that nobody knew a thing about until Delutaya made it public knowledge with her post. There was zero reason for it to have ever been a blip on 4chan's or 5chan's radars and turned into a public spectacle.