>>67840434There's a few things to consider here.
Firstly, hololive and nijisanji have a lot of vtubers, and it's not feasible from an economic point to give everyone super expressive models, the most they can do is give the new talents that join, better models, but not that better that it would overshadow everyone else, there needs to be a baseline, not too shitty, but not amazing either, then try to bring the older models to that standard.
Keep in mind they started doing this on a time when the Live2D didn't look that amazing, look at a 3 or 4 years old video of a Live2D vtuber, they look retarded compared to what we have now. Indies starting now have the luxury to start with all the improvement that happened to the software since then.
Secondly, making a good expressive model can take a lot of time to make, time that a company doesn't have the luxury or even the incentive to do, nobody knows if that vtuber is gonna be the next big thing or a 3view. So, as I said before, they keep a baseline of quality. Indies can wait even a year if it means they can get the best the money can buy.
Lastly, it can be a problem with the streamers themselves, watch this video and your own conclusions.
https://www.youtube.com/watch?v=IaPvDXeQOko 
