Apps aren't the problem? Rubbish!
"All of the top 50 free iOS and Android apps for which there are Windows desktop apps already exist as Windows Phone apps."
Is that a surprise? They are massive, adding an extra platform is not an issue in expense or resources. And if it is I'm sure Microsoft will help.
This is meaningless. My app portfolio will contain a number of these apps. And by definition these will appeal to global/general interest need. But then I have apps specific to my needs. These can be country, region or even town specific (like local buses). They will be to specialist tasks related to my skills, employment or hobbies. They will be low volume, they will be vital, and all of us will have a different set of these. They aren't on Windows now, they won't be on Windows till it has volume and Windows isn't going to have volume till it gets the apps. Not the 50 big 'uns but near the whole portfolio.
Otherwise you are offering me a significant reduction in app functionality. I, and I guess most others who have a choice, will decline the offer.
The alternative would be for Windows to run Android or IoS apps in an emulated environment. That's how it was done by companies smaller than IBM in the distant past. Whether Microsoft is man enough to do it with Win 10 should be interesting.