Earlier quoted context omitted.
If one unethical junk already exists, why another needs to be created and specifically in HTML? Let's keep the Web clean.
To play to devils advocate - because that other unethical junk requires additional downloads and poses multiple security vulnerabilities. Right? Why wouldn't a sort of 'native plugin' be better in every sense of the word for the end user?
DRM by definition implies security and privacy risk. Focusing on minor issue (native plugin) while ignoring the major one (DRM) sounds strange. And in reality this whole EME thing won't even remove native DRM code. It just will hook it into JavaScript. The risk caused by DRM won't get any less than it is already.