Even if you create a separate email address for every account, they all still identify to your domain and the surveillance corporations can link your accounts together to your identity. So I’m not sure about having own domain name…

Have your own domain for email relationships that already have to know who you are because of the nature of the email. This is the email box/account you actively monitor. Have another “leaky” free email account not attached to your name (hotmail, gmail, etc) that you send garbage to that you need to be able to receive email from, but that you don’t actively monitor.