I think if there is a breach, your email address being known is the least of the concerns. The benefit is more in linking you between sites but that's probably happening anyway with various tracking cookies or if making purchases, your credit card. Also IP/browser finger printing will be used to track you between sites.
There would be a very minor benefit in reducing exposure to a credential stuffing attack, but so minor compared to using MFA on your accounts as well as different passwords.
Not saying there is no benefit, but in the grand scheme of things and IMHO, the effort isn't worth the minimal benefit. However, everyone has a different risk tolerance.