>>22134134from a business point of view, there's zero advantage to collabing with a competitor if they are after the same core audience. they definitely have hard numbers to back this up.
vshoujo has a completely different demographic so collabing with them is advertisement for hololive.
otoh there's zero growth to be gained from collabing with niji. it might even steal/convert some of the holo only fans and split their attention.
if you watch twitch streamers, they very open about this "meta" and some of them show how the analytics work before they collab with people.