Description:
when a user encounters a problem with his wallet (possible phishing site connection…) , and the wallet has many connected websites, it may take a very long time for the user to manually delete all the connections one by one.
Purpose:
For emergency safety : Create in the Wallet the possibility to revoke all permissions & websites in only One single clic
Being connected to a site only allows that site to prompt your MetaMask with a transaction. If you already gave a token approval or signed a malicious transaction, disconnecting from the site would only prevent new transactions from being presented to you.
That being said, it would still be a nice feature for a “tabula rasa” kind of scenario.