AWS could be hacked... but the other logical options are your email provider was hacked... or some other PI/hacker who really cares about you (due to team fortress) has figured out your naming pattern from other sources and is probing you, either with or without that domain name company's help?
Considering you're a developer of a game called "team fortress" (based on your HN comment history) who had a domain for team fortress with WHOIS info updated in 2021, I'd say that its probably someone on your dev team trying to make a few bucks and knew the address. But maybe you registered this with Cloudflare and forgot, and Cloudflare is forwarding the email to you.
Are you certain you did not use the email anywhere else, including in WHOIS records for any domain?
Is the email predictable?
I use a dedicated email address for AWS and I have only ever received AWS correspondence to it.
Did you use this site to register for GoDaddy by any chance? Or for a domain name with AWS that later got transferred to GoDaddy?
Do you use browser extensions that could collect form data?
Have you ever had any domain registered with this AWS account?
This is almost certainly leaking without you realizing it via a WHOIS contact email somewhere or another
Another possibilty is that overseas contractors for AWS regularly harvest email addresses from the support UI and spam them. Wouldn't surprise me, but the first is more likely. Wouldn't really call this a hack though either way.