The claim I think you're referring to is in two parts:

1) They were willing to sell DDoS protection to DDoS services

2) This decision was made specifically because the existence of DDoS services increased the value of their product

This was always a weird claim, because the first part is 100% true -- while the second part was always unfounded speculation. The conclusion is thus most likely false. They just didn't want to incorporate that sort of thing into their ToS or vet their customers in that way, for various understandable reasons.