for me it sounds like you actually do not want to communicate via E-Mail (for obvious reasons) but require one for registering with a service that you actually want to use. Can't you use a throw away E-Mail to register at the service? Something like the anonbox from the Chao Computer Club: https://www.anonbox.net/de/

That way you can create an account with a throw-away Email and then use the account without any linking to you. But be sure to use an anonymuous, non-trackable wayy when creating this throw-away mail and also while using the service you are registering for.