So, I've been thinking for a long time now that GNOME's problem is marketing. Most platforms have worse software than GNOME, the engineering is ok. Translations are world-class, but marketing? Oh My Goodness.
Now, if I look at those 3 groups you outlined, they fall into 3 categories when they talk about their OS: The first group writes blog posts and articles and even builds whole websites around this, and the other 2 groups just go "What's an OS? Why should I care?"
That in turn means that you have to market your OS (at least on technical grounds) exclusively at the first group. In fact - and that's what Fedora found out - if you rely on contributors, they will only come from that first group. So I would argue that the other 2 groups do not matter at all for the success of GNOME.
But what has instead happened in the GNOME world is that we use the silent majority (your 2nd group) as an excuse whenever someone complained. When someone complains about the removal of their favorite feature, we tell them "it's confusing for the majority of users" - usually without being able to back that up. I have not seen any numbers at all. We don't even think about collecting any data.
And why would we? We convinced ourselves that we are the spokesperson for the silent majority, so we know what they want. And without data, we can never be wrong. Because even if all the people on the Internet complain to us in unison (ie your first group), we know we're still speaking for the huge majority. How could we be wrong?