A card, either Mastercard or Visa, operated by a centralised organisation. It means even if they don't have your KYC, they could still freeze your funds anytime. Out of card providers, still the company that issued the card for you could freeze your funds as well. For example, I have been using the Redotpay Visa card through its KYC service. In such a case, Visa and Redotpay both could freeze my account with the funds. You really can't use the card without any centralised organisation. When the issue is about freezing funds, it doesn't matter whether you use a KYC or non-KYC card.
It is actually quite standard for the card issuers to freeze funds in a debit card (KYC or not). For example, if the payment wad declined because there was no balance, then the issuing bank might take security measures such as simply deleting the card, and the service provider may or nay not return the assets to your account automatically. Sometimes you have to open a ticket with the platform.
This happens in order to reduce the chances of fraud succeeding.