So, how can one avoid a situation like this where people send money to your address with a vicious timelock.
That's easy to avoid: don't create addresses with a vicious timelock

But it is an interesting way to scam. Create said address, send funds to it, keep selling the private key.
P. T. Barnum:
"There's a sucker born every minute"
Think about it, how many people are greedy and just don't know that this really cannot be undone.
If the person who created this and sent the funds to it sold it 100 times between $500 and $1000 they have made a lot of money.
Sigh....humanity.....
-Dave