Blocking cryptominers or other script isn't possible because of JavaScript's nature as Turing-complete language, much less with new shiny WebWorkers/PWAs. It's also not just a minor annoyance when miners, trackers, and all kinds of other nefarious or just plain garbage scripts drain your batteries and consume power/bandwidth for no other reason than browser vendors being busy to develop webapp platforms and world domination schemes rather than declarative and privacy-focussed content consumption/authoring ... browsers.
I think Digital Ocean shared your view, until recently, when false positives caused them to shutdown a customer business, and a broken support procedure caused them to keep it down. Search HN archives for Digital Ocean from the last week or two and you should be able to find that story.
