Yeah, you would probably get past it like that, good one. Steganography could also be used to exfiltrate data. The point of these systems though isn't to stop

Yeah, you would probably get past it like that, good one. Steganography could also be used to exfiltrate data. The point of these systems though isn't to stop a determined attacker on the inside. It's to prevent people foolishly, accidentally, or intentionally (because they're lazy) from sending potentially sensitive data out. This happens all the time.