Ok but if that's your only criterion then drug dealers, conmen and outright bank robbers have found a way to make themselves a living.
Attracting the best talents by offering them more money and better working conditions, what a dastardly Jewish plot!
Lots of vtubers are young and naïve; for many it's their first real job. A lot of them accept contact terms that are anywhere from exploitative to outright illegal, because they don't know any better and they get gaslit by a shitty fly-by-night corp, or worse, nijisanji. Having a decent "standard" contract be publicly known will help the talents and be better for the long term health of the industry too. It doesn't stop talents from accepting a lower cut or worse terms if a different corpo is offering them something they want, but it means they can weigh up the options with their eyes open. Of course Aviel benefits too, but that's exactly how it's supposed to work.