Rudi (ryjelsum)i figure that this is worth a cross-website post:
some verification process that netflix has put in place to seemingly cut down on cross-household account sharing is a pretty significant photosensitive seizure risk, it sounds like
this is very much a tangent and besides the point so i'm not going to go poking at OP for information about what their network setup is like, but if their four different wifi networks are four routers all going to the same modem upstream then it sounds like netflix also might be sending the names of wifi networks or private ip addresses back to HQ which sketches me out but is not really surprising to me given the kind of lengths that netflix has been going to in order to cut down on account sharing
e: just want to emphasize that this is very much theoretical, and i don't really have a way to test it myself
enough people are speculatively responding to this that i went ahead and asked OP what's up with their network for more information. haven't got a response yet and frankly it sounds like OP wants to forget and move on which is very fair but if they give me any info i'll relay it since a fair few people are curious about this from a technical perspective it seems like
answer is that OP has two ISPs and that is what is seemingly triggering this. so it's kinda just a false positive of assuming one IP = one household it looks like. and it looks like the devices are smart TVs. so probably android based right? idk smart TVs since i have no interest in them. i guess that squares with my assumptions though.
the smart tv aspect is a complete unknown though because i would guess that they come with a netflix app preinstalled and it's not precisely what you would get from the google play store on a generic android device
i turned off the notifications on this post so idk if people are even passing it around still. i just know people like to probe at these things and see what companies are doing and it sounds like this is 'just' a false positive from slightly aggressive bad assumptions of a household only having (up to) one public ip address.
but regardless the verification process the OP describes is very weird, the precise manner they describe (a series of QR codes flashing that they had to record) suggests they're like, trying to establish that the person's in that place from that IP address in real time. weird shit either way