I'm a living testament that this is not true. I don't have captcha and I was affected by the halved base payout only briefly. I have not deposited at least 3M satoshis and have never lost on Multiply whether on purpose or not.

What everybody is missing, the key here is that deposits MAY help, but for example if this is your first time depositing and the amount is low it may not help. Playing Multiply and buying lottery tickets may also help. Like @TheQuin said those are one of many factors involved in determining the probability of abuse.