This doesn’t feel right to me: Mark Cuban is obviously a general target because he’s rich, but there are probably (tens of?) thousands of people not as rich as him who keep similar amounts of cryptocurrency in hot wallets. That’s all that matters to these specific attackers.

So, if you end up with a lot of money, it wouldn't be wise to keep most of it in a crypto wallet.

Crypto, perfect, as long as you don't have too much money.

Why would you target a high wealth individual who has the resources to hunt you down?

Bank robber Willie Sutton was once asked by a reporter why he robbed banks.

Yes, and he was in custody at the time ... where he spent half of his adult life.

Do you believe the people stealing cryptocurrency to be in compliance with the law?

No, I believe them to be out of compliance with good judgment --- kinda like Willie Sutton.

It's not that hard to be too stupid to realize you're going to get caught without being too stupid to realize that rich people have more money than poor people do.

Sorry, this is just a variation of security by obscurity.

"Be a small target and hope for the best" is about the weakest form of security and does not instill a lot of comfort or confidence.