Re: People stopped dual-booting 20 years ago.
I really hope you don't work in IT. Because in 1998 VMWare was still being founded, and Parallels only came on the scene in 2006.
Even in 2018, GPU-related things don't work well in virtualisation (Parallels doesn't support modern OpenGL). And these days, GPUs are no longer just used for gaming.
So no, dual-booting may be defunct in certain areas of IT but even outside gaming, it is required in others.