Here's a recent example of the short meta working well with Rin Penrose being well above her genmates in subs due to these
https://www.youtube.com/@rinpenrose/shorts

Even by looking globally at vtuber videos now, all the top watched content is all shorts (you can choose to see for last month or last week to see that trend is still ongoing)
https://www.youtube.com/results?search_query=vtuber+&sp=CAMSAhAB

And finally a bunch of channels that have been successful by doing shorts often
https://www.youtube.com/@Punkalopi/shorts
https://www.youtube.com/@jingburger/shorts
https://www.youtube.com/@AmakamiKonomi/shorts
https://www.youtube.com/@filianIsLost/shorts
https://www.youtube.com/@aogiri1027/shorts
https://www.youtube.com/@nitowai/shorts

The point is that it won't be long until the industry is gonna catch up on this and make your oshi do her daily shorts, will you be ready for this to happen?