You're not getting it, are you?
Let us be clear here. Me not agreeing with it, me not supporting it, me advocating actively against it; none of that means I don't understand the base issues and why Microsoft graciously supplies a Facebook App for Windows Phone users...
Microsoft *wants* to sell to the Facebook crowd. It's *their* decision to make the app, because *they* want to tap into that market. And, to answer your question: if not? Then they can't sell to the Facebook crowd. Obviously it is important enough to them to put resources into it.
Personally, I don't care if there's a FB app or not, I freakin' hate FB. But I'm not so short-sighted that I can't see 556 million daily users as a sizable market that would be stupid to ignore.
See? Now you used verbiage that the Facebook gotta-haves will not. Microsoft WANTS to. I agree they wanted to and will further stipulate that they will continue to do as much or as little as they want to in terms of supporting Facebook use on their mobile devices.
That isn't the issue here in this thread. The OP wants Facebook integration so deep it must be baked into the OS in a non-removable way. I say no.
Many staunch Facebook users state quite clearly Microsoft MUST support Facebook use by providing an App, updating the App, fixing the App, concentrating on the App as if Facebook should somehow be a priority for Microsoft. To this also, I say no. And when questioned why Microsoft needs to prioritize Facebook more highly; the answer is invariably, "I want it," (at which I snort in derision) or, "users will flee in huge numbers and Windows Phone will fail." To this last, I demand that some sort of legitimate statistical evidence be brought forth.
What I vociferously object to is the notion that someone is holding a metaphorical gun to the head of Microsoft so they just better fork over the Facebook and at a level that satisfies FB users in a most pleasing way... Please. It's just a time waster, like so many other things we do on our smart devices because they have so much superfluous capacity above and beyond comm and connectivity.
If Microsoft knuckles under to this sort of pressure, where does it end? Why would any 3rd party service write Apps for this platform when Microsoft will take the effort and expense onto themselves? What's next? Twitter, Instagram, Play Station support?
No, it's "Microsoft WANTS to, because no one else will..."
Wants to? ABSOLUTELY. And at their own discretion and level of support.
Have to? Must? I call BS on that. Calm down about your toy and go peddle your boogeyman stories somewhere else.
Microsoft NEEDS to make a Facebook app because Microsoft WANTS to sell phones to Facebook users. It's... that simple.
I don't buy that idea of Windows Phone loosing huge numbers if they don't prioritize Facebook highly. Show me.
On a personal note... I will not ever have the People Tile on my Start Screen in any size other than smallest. It makes it wink the Facebook symbol at me when the portraits flip even though Facebook is removed from my phone. This is just ridiculous. I purchased a Windows Phone (actually the third one now in about a year) not a Facebook phone. How much more love and support do the Facebook people want? Why is what Microsoft gave freely not ever enough?