Just how do you know what these companies are using for fighting abuse (fake accounts, spam, account hijacking, etc)? Dealing with abuse is an adversarial proce

Just how do you know what these companies are using for fighting abuse (fake accounts, spam, account hijacking, etc)? Dealing with abuse is an adversarial process, where both sides are trying to adapt to what the other is doing. It's not like most programming where you can come up with a provably good enough solution. It also means that time is a valuable resource. There's nothing to be gained by e.g. Twitter announcing that they're now using ML on the profile images to detect fake accounts. That'd let the bad guys know right away that they need to change their pattern. Instead what you want is for them to first waste some time before they realize that something is wrong, and then waste more time experimenting on exactly what changed, and then even more time figuring out how to bypass it. So unless you're working on abuse at one of these companies, I don't understand how you can so confidently talk about what they are and aren't doing.