I don't understand how posting a "wallet code" is dangerous. Is it mining coins while you are browsing the code? Then it just a minor annoyance. Also, browsers should block cryptominers when they are in the background tab.
I would wager most of the people dealing in crypto currencies are actually precisely the kind of people that would fall for pretty much anything. I don't think it's a stretch to say that the fact that they deal in crypto currencies is actually a pretty good indication that they would.
More to the point - there is a significant number of people who started learning about computer security precisely because they got some cryptocurrencies. And frankly, if someone wants to really understand the details, it's hard to miss all the frequent warnings and examples of scams, hacks, leaks.
I saw one of those fake Elon Musk posts in my stream and my first thought was "Wow! Is Elon pushing shady blockchain money things now?" It wasn't until a few seconds later that I realized there was no blue-check and it wasn't him....
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.