>>3196773There is more to sponsorships than money. For example, connections, and attracting bigger sponsors that go out of their way to request you play their stuff, complete with early access, instead of you having to beg for the permissions. Networking with the gaming industry looks a lot like a war of attrition as opposed to forging connections with fellow vtubers and doujin musicians and artists.
Look at how Pekora draws crowds and attention to whatever she plays, a select few gaming companies figured that one out.