The glee about Quibi's failure seems to me misguided. Startups are hard. There's no honor in applauding when they fail. To me it's impressive that people so established would undertake a project so risky. Especially considering the probable reaction if they failed.
It's only reserved to the extent the PE firms' agreements with their LPs restrict them. Otherwise they're free to invest in whatever they think will generate the biggest returns.