22 years and counting. 99.999% of my spam comes to emails in various leaks.
I get possibly a dozen or so emails a year to catch-alls that I dont recognise as having been given out - its incredibly rare that it is every anything other than someone mistyping my name.
I also get a monumental quantity of spam so not exactly a small sample but still just one example.
I haven't really been analysing my spam thoroughly to be perfectly honest, it is possible this has happened to me and I didn't notice it because the Gmail spam filter caught it.
I do pop in every now and again and don't recall seeing anything akin to what the parent to your post is suggesting (many emails following the same format but to different addresses and I guess names).
tbh I thought it would be a problem when I set up - <trillions of combinations of letters and numbers>@mydomainname.com - thats going to be a lot of email. It turns out that nobody knew I existed so didnt get all that much spam for years. Back then slapping your email on your site / forum footer etc was the way to get on the spam mailing lists.
Then along came web facing databases with no auth defaults, and you can have a billion active, in use email addresses with a living breathing human at the other end (and their username, password and dob) for free.
Back in the 1990s, a spammer who knew example.com existed would bulk e-mail a dictionary of prefixes - andy@example.com, bob@example.com, claire@example.com etc etc in the hopes that some would get through.
As such, a catch-all e-mail address was a sure way to get hundreds of copies of the same spam e-mail. And since most people who wanted a catch-all address were doing it as part of a strategy to get less spam, that was the opposite of what they were aiming for.