Is a macbook pro from 2006 with linux on it :). Good luck trying to surf the net with safari on Snow leopard Mac os 10.6 , which incidentally i had to reinstall before i could transform it into Linux! I use the browser to get me i believe rEFind by roderick w. Smith. That was an experience, i tell you. The DRM stuff is not s problem on firefox after you install the packages it needs.
Note that the parent may not be referring to 4k, but mere 1080p. You only get 720p in browsers except for Safari/macOS, Edge/Windows, or Chrome/ChromeOS.