Ah, that's surprising, Microsoft was very stubbornly not doing that for at least a decade and a half.
In fact, the FAQ in TFA (questions 9 and 20) mentions that there are still problems with CP_UTF8 (65001). Is the article out of date? Can someone respond to those statements?
The article is outdated, it's from 2012. Not only they fixed the problems but in Windows 10 1803 they also added an option to globally and permanently set both OEM and ANSI(!) codepages to 65001.
It can be enabled by checking "Beta: Use Unicode UTF-8 for worldwide language support" checkbox in region settings.
In fact, the FAQ in TFA (questions 9 and 20) mentions that there are still problems with CP_UTF8 (65001). Is the article out of date? Can someone respond to those statements?