You can kind of do this with Fastmail and Aliases, but it's a more manual process.
You can really easily create aliases for specific sites or just a general spam@ alias on your own domain. Then if it gets abused you can mark all mail directed to that alias to bounce.
I migrated from Gmail to Fastmail 2 years ago, and I agree with this. With Fastmail, I now have the wildcard address for a domain ([a-z0-9]{7}@example.com), whereby I create a new randomly generated email address for each company/site/contact. I set up rules to direct emails sent from expected addresses (sometimes by base domain regex rather than a single address) to whitelist emails to show up in my main Inbox folder. eg. My HackerNews email might be qvae82d@example.com, whitelisted to accept emails from *@ycombinator.com to my main Inbox.
The thing is you don't want to completely blackhole/delete messages received at a valid randomly-generated address, but which were sent by an unexpected sender. For that, I have a separate "Suspicious" child of my main "Inbox". The main exception I've seen that falls under "Suspicious" is that Amazon shares your account's email address with their shippers; so you'll receive a Fedex delivery notification at your Amazon address, which falls under "Suspicious" because the sender address doesn't originate from Amazon.
What I find mildly strange is that, in the 2 years since I've migrated from Gmail to a super-organized and rules-based organization with Fastmail, I have literally not received a single spam email. I credit this to having migrated my GitHub account to use their privacy wrapper, so none of my commits have a personal email attached to them. I thus suspect that most developers who receive spam have had their email crawled from commits to public Git repositories.
Of course, there is a caveat: I do not expect to be able to maintain this kind of scheme into old age. There's no way, at 60-70-80-90 years of age, that I will still be mentally capable of managing a wildcard domain. So while it works for now... at some point I will need to simplify back to a single email address. Sigh... fml in advance. :(
> There's no way, at 60-70-80-90 years of age, that I will still be mentally capable of managing a wildcard domain.
Do you think this will get technically harder and you'll no longer be familiar with the "new" process? Or are you more worried about your mental capabilities in general when you're that age?
Most of us will wind up with some form of mental or physical degradation… that may mean Alzheimer's, or Parkinson's, or psychiatric conditions, or horrific cancer (eg. prostate, breast, uterine, COPD/emphysema, etc.) that weakens us for months or years at end-of-life. The fact is, there are so many things that can go wrong regarding health in one's mid-to-late years, that expecting to manage a complex identity/password system is unrealistic.
I did this a while ago for myself; it looks like the setting can be found here[1], labelled as a checkbox "Keep my email addresses private". Note that (I think, not sure if it gets overridden if you check the box), you also need to set your "user.email" git config to use the noreply email they provide. Personally, I'd never committed to an external 3rd-party repository, and I crushed/re-imported (erasing history) my own repositories using the new noreply email. This is because I know no external users were depending on my old repositories. I suspect that if you've already pushed commits to a 3rd-party repo, it's too late (the email address is part of the commit and cannot be revoked without a history-changing rebase). In my case, I deleted my repos and re-imported, history be damned.
Ah thanks - yeah I've already pushed with my new aliased email for git (I recently switched to Fastmail and set up a less extreme alias configuration :) ).
Could this be automated, e.g. by a browser extension or a small app setting up an alias and an ding a site-specific rule to your FM account? I am thinking about a one-click sort of thing, a DYI alternative to Sign In with Apple.
You can really easily create aliases for specific sites or just a general spam@ alias on your own domain. Then if it gets abused you can mark all mail directed to that alias to bounce.
You could later re-enable it if you wanted to.