We're in a new era of software, where the Internet has allowed developers to release code in near-beta and patch later. It's not just Microsoft, everyone does it now. No, that doesn't make it okay that everyone does it, but they all do it. It's just the reality of the time we live in. Every desktop OS, mobile OS, and most software/apps are released with bugs and patched as time goes on. The past 12-13 months saw two major PC game titles released with so many flaws they prompted formal apologies from the companies and either refunds or free gifts (Assassin's Creed Unity / Ubisoft, and Batman: Arkham Knight / Warner Bros). Both major consoles (XBO and PS4) had large "Day 1" patches, meaning you were welcomed to your new purchase with a patch. OSX, Windows, and Linux have constant patches, service packs, minor updates, major updates on a regular basis to fix bugs and add new features (which usually have bugs requiring further updates). Major anti-virus companies release updates that destroy computers. I could go on and on... It's the era we live in.
Calling Windows a SaaS is a marketing tactic. Remember that - everything that comes out of a company's mouth for public consumption is marketing. Microsoft is changing how Windows is being released to something similar to Apple. Instead of Windows 7, then a few years later, Windows 8, then a few years later Windows 10 - they are releasing 10, then 10.1, then 10.2, then 10.3, etc. Instead of calling them service packs, they're calling them code-name releases. Windows 10.0 was Threshold. 10.1 will be Redstone, etc. And each code release may have minor updates as well, such as Threshold 2. And Microsoft doesn't charge for those updates, just like Apple doesn't charge for OSX code-name updates.
Now to Windows 10 Mobile. There is a reason it hasn't been released yet to phones, MS doesn't feel it's ready. The reason we have the 950 and 950XL is for the fans (or FANBOYS as you lovingly call them). It has always been said by Microsoft that the 950 series was for diehards - MS's way of thanking them for sticking with the platform. It was never meant to be a mainstream phone designed to bring people to the platform. It's not being advertised, and not really being pushed by carriers. It's for the fans. People who, in all likelihood, were in the Insiders preview and had Windows 10 Mobile running on their daily driver or backup phone for some time. People who were prepared for bugs and testing, and used to giving feedback.
If it's just for the fans, then why did they pick a carrier in the US to adopt it? They could have just sold it online and unlocked only. I don't have a definitive answer for that, only a speculation. They needed to test the idea of forcing updates to the phone without carrier involvement. They went with the company that started the revolution with Apple. If it succeeds, they have an "in" with other carriers when future mainstream phones are released.
Yes it sucks that Windows 10 Mobile has issues. And yes it sucks that you had to pay $500 for a phone with issues. But that was always going to be the case. The 950 hardware was a gift to fans. High-end specs with access to the latest builds of Windows 10 Mobile.
I think where Microsoft is heading is an excellent vision. I'm frustrated with bugs, but I also knew what I was getting into. I also see that Windows 10 is being updated faster than I've ever seen an OS updated in the past. It seems that when I have a major frustration it's solved within a few months. I hated Groove when it was first released, but now it works 10x better for me and I enjoy it daily as my music player in the car. I was frustrated that I couldn't set custom ringtones and text tones for contacts, but a few months later ringtones was fixed, and a month or so after that text tones were fixed. Battery life was a problem in the beginning, but has gotten better for me with each update.
I know that people need a place to vent their frustrations, and these forums are excellent. There are people here who genuinely want to help others with their experience. And there are people who genuinely want to ruin other people's enjoyment - and rage against the machine. It's okay - we work together.