No one says you wouldn’t encrypt on prem too. It just adds the extra layer of difficulty slurping everyone’s info all in one go. Someone would need to actually walk to the customers site and all to take their servers, potentially.
Remote access is a good point, but most commercial sensitive data (medical, manufacturing, etc) is location use restricted anyway.
People whose livelihood currently comes from businesses whose primary source of income is in selling people's data don't want to even think about the idea that doing something else might be a better idea.
There are a lot of people in tech (and, quite likely, on HN) who work for companies with such a profile. (Just for instance, everyone working for Google, Facebook, etc.) I doubt it's a majority, which is why the comment appears to have returned to a positive score, but there's certainly a strong contingent that could very well feel threatened by the idea that we might, as a society, have to abandon profiting off other people's data as a business model.