Windows Media Center had/has this feature (although it was more like 1.5x or less). I think it's a great feature and use it quite often with WMC to get through boring sections of a show or simply watch something more quickly. Especially good for talking head shows.
I still use WMC for OTA recording, because I can't find any replacement for the Movie Guide it offers. many WMC replacements offer channel guides, but you can't filter for only movies, as well as sub-categories. However, I've never used WMC for playback, so I can't say for sure what playback speed options are still available. And it may or may not be able to do that with a DVD/Blu Ray. It might be limited to media files (ripped discs, recorded TV).
Dan Roku Stick (3600), Ultra (4640), Ultra (4670), Premiere (3920), Insignia 720p Roku TV, Sharp 4K Roku TV, Nvidia Shield, Windows 10 Pro x64 running Serviio and Plex on a wired Gigabit network.
Just being a file at all makes it physical too now. Whether its streaming, saved on a cd in your hand, or saved on a server at Netflix-- those bites live somewhere. And dont even get me started about photon particles.