I have a Yahoo mail account. Haven't used it as my regular email account for years (circa 2007-2008), but I've kept it for certain purposes that would have been a pain in the ass to change.
One pain in the ass seemingly associated with most web-based email services is that they make it very hard to clean house in a big way -- like deleting every last message when the total comes to six figures.
Last week, I decided to buckle down and do that with my old Yahoo account, with a view toward maybe using it for more things and possibly even transitioning back to a main email account with my name on it instead of the name of a campaign I ran eight years ago.
It took several hours (and I am still monitoring it to cancel the odd list subscription, report spam/phishing, etc.) but I eventually got to "your inbox is empty." Root and branch. Scorched earth. A completely virgin email account.
You've probably come across the report that Yahoo "last year secretly built a custom software program to search all of its customers' incoming emails for specific information provided by U.S. intelligence officials" by now (if not you should consider subscribing to Rational Review News Digest).
Sort of the opposite of serendipity.
It would really bother me ... if I didn't assume that every other web-based email provider of consequence has also received, and complied with, the same demand.
But yeah, that's what I assume.