Below the main post:

"since this got boosted if anyone happens to know about service manuals for appliances, lmk. i’m textin a buddy about this and now we just wanna kill it instead my backup plan (forever dhcp lease + block IP from pf.conf). even the manuals i can find online from samsung don’t mention the smart features, it seems to be more of a “don’t burn down your house idiot” thing "

It seems their plan was to block it at a network level if they couldn't do this.

Changing router means you have to re-block. Plus nothing better (more reassuring) than an actual air-gap from the internet.

After I cut over to a new wifi router I left my old one partially configured with no internet connection and mirroring everything to one of the LAN ports that goes to an un-numbered (no IP address, no IP egress) port on my main server where I can maniacally sniff their futile unrequited traffic at my leisure.

The idea is to some day make a per-gadget catalog of all the hostnames and addresses these things want to reach, but hopefully someone beat me to it already and you folks can let me know where to find it.

Or don't enter your wifi credentials to start with?