Emulators are useful. I'm sure I've done some courses that did that. The data science courses used Jupyter Notebooks that run code on their servers, so you didn't have to install anything. For the next programming one I needed to install stuff, but not a problem so far on Linux.
Videos can be an issue if the instructor is not engaging. Some people are just boring to listen to :)
Hehe, they are. I think it was mostly on pluralsight that I started to find it an issue and all the instructors there are awful to listen to!