I don't quite understand what it really means to burn tokens. Since the blockchain is immutable, there should be no way to delete the record. Thus, in my understanding, to burn the token merely means to send it to the address without the private key or the address that has lost its private key.
However, token issuers claim that the value of a token goes up because they burn tokens.
Are they actually burning tokens in any way or am I right that there is no way to delete tokens?