Regulations that limit the ability of investors to invest in private companies, although these have been weakened in recent decades, which helps fuel the growth of private credit markets that allow private companies to stay private.

I'd say it's the growth of private markets to allow companies to keep getting funding even at the $100 billion range while staying private that has fueled the trend to stay private rather than SOX and other new regulations for public corporate governance dissuading them from going public.