I wish more companies did this. I cannot delete my Coinbase account because I must provide a phone number to log in (which was not needed when I made the account). SendGrid does the same thing.
Yahoo handles it well, I think. They will send an email to your recovery email address to inform you that unless you log into your account in the next 30 days or so, it will be closed.
Worked OK for me with the default context size. 2048, like you see in most examples was too slow for my taste.