They ban thousands of accounts per day. Every day. If you can solve this problem you will have discovered a license to print money, so by all means try. But the problem is much harder than you are making it sound.
On the other hand, how many do you think would reach out when they get blocked? Most actual fraudsters wouldn't. Of those that do, you can take a look at what they are sending and quickly see if they are actually doing fraud or not.
I could say the same thing to you, you're making it sound harder than what it is. But if you're set to the mindset of saving money, I understand minimising work makes sense.
Of course they do. It’s just email/twitter/telegram/WhatsApp, and fraudsters are literally professional messaging automators. They open support cases, email execs, I have seen cases of them paying call center workers to call support lines and complain. Fraud is a serious business run by serious people, many of whom have a decade plus of experience.
You cannot attempt to stop fraud with manual effort if you operate at any kind of scale. Full stop.
I could say the same thing to you, you're making it sound harder than what it is. But if you're set to the mindset of saving money, I understand minimising work makes sense.