The Gmail spam filter filters out emails from Google, half the 2FA authentication emails I get, things I’ve actively subscribed to and hit “not spam” on several times, and does not block “You’ve won a Home Depot gift card!” from h3uu3hb382jeop1fe@je7qow.xy
I set it once like 6 years ago and forgot it wasn’t something pre-installed and configured until I saw your comment. I was reading through the comments looking for the “you don’t need to do anything, ddclient takes care of it”