But, as I said above, we are only hearing about it because it's BTC Had it been The DaveF & ranochigo Jet Engine Repair Company, it probably would not have even made the news.
You sure, maybe in the US, meanwhile here in Europe:
https://www.euractiv.com/section/agriculture-food/news/france-passes-law-to-protect-farmers-against-townie-complaints/With thousands choosing to move to the country side the whole of Europe is flooded by lawsuits of people suing farmers for noise, farms that have been there for generations, and yeah, we're talking about being not able to sleep because of cow moooos!
Try building a mining farms here!
i don't even think sound walls do anything. they might make the sound a little less loud but they probably don't cut it out entirely. and immersion cooling won't do anything either. since the source of all the noise is the fans that are exhausting the heat from inside the building to the outdoors. you still have to do that with immersion cooling.
Sound is nothing magical, put enough mass in front of it and it will stop, reflect enough of it and you won't hear it.
As for cooling, it's a matter of airflow, you have the same heat but it depends on what area you want to dissipate it, two tiny fans going at 6000 RPM at 250 CFM in a metal box will be loud as hell, put 20-inch blade on that thing and you don't need the same speed for the same airflow. Also, you don't have the same area for the exchange so more area less volume of air per same surface.