Preface
For as much as I want to read all 150+ posts that have come out of this discussion, I’m going to voice my opinion on it’s own for the sake of having my say and giving perspective from the Marketing Team (I’m not speaking for the Marketing Team of course).
I’m grateful for @catanzaro’s respectfulness in the proposal and with the replies I’ve seen. Given the circumstances, I want to make sure to affirm that. Respect to @cassidyjames too because I know this is based on your work on Endless OS. Sorry for the lopsided reaction. 
To acknowledge my bias, I don’t want to see telemetry in Fedora at all. That’s my preference, but that’s not the perspective I’m writing from.
Preserving the Fedora brand
When people think of Linux, it is usually in contrast to Windows and macOS. Linux users are looking to gain control over their systems and avoid telemetry that many times can’t be removed from those OSes. Linux has the reputation of being private. Fedora Linux specifically has risen to be recommended as the most private and secure Linux distro for desktop. Through hard work and dedication to openness and user privacy, we have an extremely positive reputation in this space.
With this proposal, we’re unfortunately on track to burn it.
I understand that part of the negative reaction to this proposal is overblown or misguided. For many, they just see the title and immediately assume that the change is already implemented and must be the worst kind of telemetry there is. Some don’t make a distinction between different ways of collecting data and what exactly is collected. In fact, some have already dismissed Fedora as spyware. The majority of those who remain are currently upset and/or scared that their distro is going to become more privacy invasive. It bears mentioning that this proposal is tainted by Red Hat’s recent decision to change how RHEL’s source code is made available, which was incredibly unpopular. This is just the reaction to a change proposal that hasn’t been accepted and won’t even take affect until next April.
Unfortunately it doesn’t matter how not responsible we are for the reactions of the Linux community. Perception is reality. Even if we implement the best version of this proposal where we collect almost nothing, all that most people will know is that Fedora has telemetry on by default. News articles and YouTube videos will be made giving their likely negative opinion on the change, which will affect interest in Fedora in the same way that influencer interest led to Fedora’s recent popularity. Only the folks who care enough to read documentation will know what’s actually going on under the hood. We will be defending this decision for years to come and likely not make serious headway, in my opinion.
Is the lose of users worth the data you gain by making this change? Is the lose of reputation worth the data you gain? That’s the tradeoff to consider. I’m not sure how to measure this. I think that we’ve been able to build great desktop environments and applications without telemetry. People are getting happier on Linux and Fedora with each year that passes. Is this telemetry proposal worth taking a wrecking ball to that momentum? Are we willing to lose the users that we could have converted into contributors over this change? As of now we are slowly getting better on our own. With telemetry as an opt-out option, maybe we get slightly better desktops at the cost of tons of users and the trashing of the Fedora brand in every Linux forum on the internet. We’ve already seen a small form of what that trashing looks like, so this isn’t a hypothetical consequence. If I was in the Fedora Engineering Steering Committee, this does not seem like a good trade at all.