I've been using Proton Mail and iOS (through iCloud+) for this. Almost every purchase online goes through a proxy, and once the item is delivered, the email deleted.

This has a side benefit of being able to sign up to the popup modals for like, 10-20% off a first purchase.

Some sites do not parse the emails correctly though (if they contain periods, etc) and it's also hard to order track.

I find it's worth the trouble to have a relatively quiet inbox.