This can be done easily if you own a domain and use a service that lets you specify a catch-all address. I do this with my own domain and G Suite. Then, you don't even need to do any preparation before giving out the address.

It does sound weird to the person writing it down and I've had more than one person say something like "well, if you're just going to give me a fake address, then don't bother" before I explained myself.

One other down side is that it is not as easy to reply to mail as the other, generated identity (in gsuite, you need to create a new account in the domain to write as that username and also maybe jump through a hoop or two). Replying casually can often reveal your main identity, which is often the one you are trying to strongly protect.