That's just the manpage in html format, are you kidding? We're not in the era of text terminals, there are so many tools for writing good documentation that this is just inexcusable. Take a look at VLC documentation (https://wiki.videolan.org/Documentation:User_Guide/), that's a proper documentation with screenshots that looks like someone actually put some effort into writing that so that it is understandable to new users instead of plugging words into a troff file.
Except for the edge case of controlling a media player from another application you've put no convincing use case for using mpv over vlc. So it's a personal preference not that mpv is superior to vlc in anyway (actually far inferior for most use cases).