This question is flawed, what you need to do is compare Subaru summer of 2020 & afterwards (she stopped maimoto collabs end of 2020) to a control of someone with a similar audience who almost never collabed with males to account for the growth of Hololive, and the right question is incredibly hard to answer because I have lectures to attend for the next 4 hours and no time to analyze data sets.
Preferably the control would be from the 2nd gen, but all of them are flawed controls because they don't stream. Ayame actually tracks incredibly well with Subaru's growth in terms of superchats, but I forgot if Ayame's last male collabs were in early 2020 or 2019.
The next best control is Okayu as she's close to gen 2 and does similar gaming content and collabed only once with a male in mid 2019, and Okayu has consistently across the years lesser amounts of superchats but similar growth of around 2x from 2020 to 2021 in terms of superchats.
This is all from a glance. Numberfags can look at hololyzer. Please don't try to use 3rd gen as a control because they're a miracle generation who were strong from the start. Try to use similar audiences & time periods
As of right now it doesn't seem from a glance that Subaru had any enormous buff or relative growth that didn't apply to members similar to her, but certainly a buff. The buff really kicked in when she had the girly suba outfit so you could use that as an explanation instead of unicorns specifically. These questions are kinda hard to answer specifically. If the rest of her genmates streamed consistently and were popular it would be way easier to answer
