I've compiled a few random screenshots here: https://imgur.com/a/S5PyL
I've always wondered this. Sometimes the font is Times New Roman (perhaps a default in Chinese operating systems?) and sometimes it is this iconic font (https://i.imgur.com/2OX6RgY.png) that is not to be found in the west.
It is so prevalent that Shenzhen I/O, an assembly programming game used same fonts in their mock datasheets: https://www.pdf-archive.com/2016/10/10/shenzhen-io-manual/preview/page/30/
https://zh.wikipedia.org/wiki/中易宋体