[1].Sending Bitcoin to a wrong address that has never been recoverd till date.
But this is how life financial life works. This is not a bitcoin protocol problem.
If you transfer money to the wrong bank account, your money is gone either. It is easy to contact the owner of the bank account, because you don't have any privacy in bank accounts.
that paying less than 10 cents of USD for a transaction which can be send anywhere in the world, censorship resistance, with a decent degree of privacy, is very cheap.
You might also be more cautious and double- or triple-check the address you're emailing to.