When I see these complaints I assume it's either they are suspected to be doing illegal business, eg, too many stolen card details, drugs, or the account-holder

When I see these complaints I assume it's either they are suspected to be doing illegal business, eg, too many stolen card details, drugs, or the account-holder themselves are in a location or of citizenship that will get the service provider in serious trouble vs US law if they continue the relationship. Often the description of what happened is missing some key points until you enquire further than the original description.