The goal of sales isn't to block upto a 1/3 of world wide traffic. Turning off Cloudfare means more traffic and more sales are not blocked. Did you even read the article or did you dismiss it because it came from 'sales'.
Sales: "look, I turned this off and sales went way up"
Security: "We had to cancel every single one of those sales because they came from stolen credit cards. It's costing us more to deal with that then we are earning"
Accounting: "We're measuring a pretty big loss because security cancelled legitimate purchases together with fake ones and now clients are leaving."