No, people can send funds to any address with a timelock on it.
Correct, but that doesn't affect me. There's nothing stopping anyone doing all manner of stupid things with their bitcoin, like locking it behind scripts which are impossible to ever unlock, or burning it entirely. But no one can lock up bitcoin they are sending me unless I first agree to it by creating such a timelocked address in this case (or via covenants in the future, etc.)
How about this? You are busy with something and someone wants to buy something from you. And with very limited access to the network, you check your address to see, ok the funds arrived, then you released the goods but it's too late to find out there is actually a 100years timelock on it..
This shit can happen.