The solution to this is unlimited true email aliases as e.g. StartMail [1] and Fastmail [2] provide. I wish this was more common place for email provider. Besides the front up cost of developing / setting up the solution, email aliases have the marginal cost of one small database row per alias. And it would be such a boon for privacy.

[1] https://support.startmail.com/hc/en-us/articles/360007297457...

[2] https://www.fastmail.help/hc/en-us/articles/360060591073