Well I've always been in the habit of having mine set to private as I'm not really even a Steam user (it's just a humble bundle code dump). Every time there's been a connect run I've had to temporarily set it to public.
During your thirteen years, did you ever check all the privacy options and make sure they were set to private, or did you just naturally assume they were set to private because that's what you did at the start?
I ask because it's possible they added extra options since 2005 which you hadn't set to private. As far as I'm aware, the recent changes at Steam were making it so that the default setting was now set to private. This means the original default must have been something other than private, so if some new options had appeared since the last time you looked they probably wouldn't have been set to private.

TL;DR: I think it's likely that your profile wasn't set as private as you thought - because lots of people did have to change theirs to public. I remember forum threads about it when connect first launched and I myself had to do it.
They couldn't. Steamspy relied on people not changing from the default, they didn't and couldn't get data from private profiles. The thing that caused them so much trouble was the change in the default. Same for GOG Connect.

@CARRiON-XCII

Thank you for that info and for taking the time to try and understand my question. Your post was very helpful as I was struggling to convey my question and confusion about what took place.

@SirPrimalform

Thank you as well. Both you and Carrion were hitting on the areas of my confusion. You could be right that something changed along the way unbeknownst to me. As far as I know I've always set my Steam profile to what I thought were private settings so that only "friends" could see it. I don't think I've ever changed anything but likely Steam settings did change along the way and according to you all, they recently changed as well.

It gets quite confusing when things are changed under the hood and you're no aware its being done. It also sounds like whatever the user end controls and options are that they are in some way limited and not necessarily hiding everything. For example the scenario where my settings were always set on the private end of the spectrum yet somehow the information that GOG Connect needed to work was still apparently available to be accessed by that service and therefore still function while at the same time, visually to myself, my Steam settings were always private/friends only. Steam's new security measures have now apparently properly hidden that information that users were unaware (at least myself) used to be visible regardless of privacy settings.

I thank you both and everyone else who helped me with my question and concern. Its very heartening that some of you took the time to actually read through my posts to understand my questions and then attempt to politely assist and expound on you answers to help me figure out what was going on. That is much appreciated. Thanks Carrion too on the suggestion of just temporarily changing my profile settings when needing to use GOG Connect and then change them back. I was wondering if that would work or not. I'll give it a try. Thanks again all.

Allow me to ask the dumb question here: If GOG Galaxy requires me to LOG IN to my account in order to set up the connection, why does it also require the information to be public? This seems counter-intuitive and probably why some people are naturally questioning the motive.

How is GOG Galaxy supposed to know, which games you have on Steam, if that (Steam-exclusive) information is hidden from the public (in this case: GOG Galaxy)?

Edit: added "Galaxy" to (hopefully) make it better understandable

Can you finally stop with all these post about Gog Connect?...


Gog already says that is not supported

This thread is about GOG Connect, not Galaxy.

GOG Connect required the information to be (temporarily) public so it could scan the list of games you owned on Steam so they knew which games to give you access to through connect.

I'm not aware of Galaxy requiring things to be set to public, but if that's a problem you're having this isn't the thread for it.

You've posted in the wrong thread.
This thread is about GOG Connect, not connecting to Steam via Galaxy.

https://www.gog.com/connect

They are two very different things, though to see your games owned at Steam, would require revealing them to GOG in the same manner for both features.

P.S. GOG Connect is currently out-of-use ... retired for now.