At the time that I stopped using the website, this was definitely the appropriate place to ask the question as there were no alternative places to ask
I'm a superuser moderator and I've been a fairly active user for 7 and a half years) - and windows phone has never been on topic for us. I've been a member since shortly after beta and this has never been the case.
There certainly have been some changes since you were last on.
We accept tablet questions (we didn't before!) due to windows RT (Which is dead), but phones have always been off topic.
I admit, many of the policies and their evolution's on meta. Stuff like our policy towards software recommendations and the workaround we prefer, or our policy towards hackintoshes are there. This though, is something that's fundamentally the same, and major changes in policy, and things in our help pages rarely change.
Its even explicitly in our "What types of questions should I avoid asking?"
electronic devices, media players, cell phones or smart phones, except insofar as they interface with your computer
This is also implicit in the original post that announced the site
At any rate, if you wanted a community where (almost) anything goes,
you’re about to get exactly what you asked for in the form of
superuser.com. If your question has to do with computers, it will be
Its not really you. We've had that attitude a lot from SO in the past, and I admit, I have trouble keeping track of the new stack sites, despite actually having been using the site constantly for over a half decade. I do check the help pages before asking a question on a site new to me, or one I've not been on a while. I wouldn't blame rules changes here, but yeah, maybe a refresher would be nice for folks who have not been here a while.
And well, it comes down to people who use a community to handle cases like this. Downvotes are not the end of the world (and I suppose some may consider not checking what's on topic lack of research). Comments let you know precisely what's wrong. You were given alternatives (flagging for migration).
Feels like our "system" worked exactly as designed, with users helping (mostly) re-educate you, and things ending up where they need to be.
I'd add though, even to this day, I always take a quick look at what's on topic on any new site I post on.