Serious answer? It's because streaming went mainstream much later than in the west. Yeah, they had niconico but that shit was a more popular
justin.tv but not "mainstream". Shit started to really pop off when YouTube picked up traction. At the same time, vtubers also started becoming a thing. By the time the livestreaming became what it is now, vtubers were pretty much entrenched in the culture of streaming as well. Nowadays, most Japanese people consider vtubing as one of the more popular subsets of streaming culture. Most people who want to start streaming probably consider using some form of live2d avatar because that's just the norm over there. That also means that talented male streamers actually have a good chance of streaming as a vtuber instead of just doing a voice showing their face. Compare that to the west where streaming was already a thing way before the Hololive boom. Not to mention animes reputation and that basically means that vtubing was immediately shoved into a niche subsection of western streaming culture. If you're a male streamer who can actually make it on your own (or you think you can), you're thinking of what kind of stream set up you want instead of what live2d avatar you can get.
