It's what felt like what really killed Windows Phone. Too many things became "only available" through an iOS or Android app. Windows Phone was free as in beer towards the end and there's a possibility there would have still been a small but devoted techie audience on it, if so many things weren't already so broken from disappearing/vanished app support.
Microsoft also effectively killed a beloved OEM phone brand as a tax write-off in the process of Windows Phone shenanigans, and famously paid developers to publish shovelware to their app store, which synonomized their platform with low quality apps. Neither were very bright strategies. Ballmer also decided to sit at the starting line for a few years and only decided to enter the race right around the time iOS and Android were taking their victory lap. Being free at the end is the easiest way to also be equated with dead. Remember the final death throes of the Palm Pre and PalmOS? They were basically giving those away right before the brand completely died.
It always seemed insane to me that people accepted so easily to have everything locked behind "app stores", crazy garbage, even worse having SO MUCH PREINSTALLED BLOATWARE OUT OF THE BOX.
> buyers have to choose between the products that are available.
That is how a free market works, however it doesn't really cover the "I need to function in society and there are no good options for this device type that have the features I care about" problem.
When your choice is between the NutPuncher 9000 and the BallCrusher 17, it's something of a false choice.
The push against technical literacy helped a lot in having the masses accept all this crap.
A great deal of people don't even understand the concept of installing software if it's not via the App Store, nor do they understand what's involved in the process. Explaining the issues of having a central authority is one degree further.