Earlier quoted context omitted.
Email providers is about who you trust to have access to your correspondence, and in terms of a company, access to customer information and any sensitive information related to operations, staff and so on. Worst provider is the one you don't trust.
I totally get that there are reasons to use proton mail and I even use it. But I was purely talking about product here. I think some people allow their feelings about data privacy and business practices to cloud their judgement about product.
It is a bit like comparing a bank, a stock option broker, and a gambling site, and discussing which provide a better product to hold your money. It make no sense comparing them unless we view them as providing the same service.