I don't use debit cards anywhere for this exact reason. Don't even have one. When I have in the past, I've had the card linked to a seperate bank account with a small balance and no overdraft protection to limit damage. What I'd found though is that even when you tell the bank not to enable overdraft protection, they conveniently forget that and it stays possible to overdraft your account and get hit with fees,

I do the same strategy for crypto wallets, there's only a small amount in my browser wallet so that if somebody gets it, they can't steal much. From there you can have varying degrees of storage security for larger amounts: multi-sig so you have to sign transactions using multiple devices, hardware wallets, and cold storage.

I see all these articles about people getting thousands of dollars stolen from their crypto wallet and I'm like, you put $3,000 on the same computer you play Zombie Run 4 on? Knowing there was no fraud protection? And that a hardware wallet costs $100? Or that multi-sig is free? If you are storing that much in crypto, you need to either educate yourself on safe storage or use a custodian you can trust (exchange, multi-sig with family member, etc) who can.