That completely misses the point. Privacy and performance advocates don’t care how hard life is for JavaScript developers. JavaScript developer convenience as the top priority results in the very slow privacy violating sites things like this browser exist to ignore.
I have worked on a web browser. It's fricking hard. Remove JavaScript and DOM entirely, and it gets much easier.
Now if you start to implement select parts of the spec, it becomes even harder when something fails to know whether it's a feature (because you don't like that part of the spec) or a bug (because you misunderstood or misimplemented some part of the spec that you wanted to implement correctly).
I agree with that about 90%. The standards do not come as a single universal package. Browsers cherry pick what they want to support or what support to drop as they can release new features. The challenge there is picking features to support but ensuring they work independently and without regression. It takes testing the incumbents have spent years developing.
