Some Apple articles will tell you not to worry if you’ve accidentally reported someone as spam, but it actually does something. It’s not a pedestrian crosswalk button.
I found this out the hard way when my wife could no longer send or receive messages nor sign into Messages and we had to contact Apple support. I’ve accidentally reported tons of people as spam because of this stupid Messages experience, and I can only guess that I’ve reported my own wife so many times from clearing all of my Messages conversations that they disabled her Messages account.
The support tech had the gall to tell me they’d reactivate her account as a one-time exception, and I practically wanted to kill the guy over the phone.