Great points that you've made. One thing though, I would argue that we've seen this issue in action: "Nahhhhh... this is like saying "We have too many car manufacturers... we all need to narrow down and settle on a couple key models"
That is essentially what the reborn GM has done - it paired down a wide range of models by their brands into just a handful. If the recovery of the company is any indication, consumers responded well to a whittled down set of choices over fragmentation set.
True, but I would offer the difference between "Too many models" and "too many models at a manufacturer (or in this case, per OS)".
GM fragmented their product line too much to offset the manufacturing and R&D costs to support all of those models. Narrowing focus was more to save their own skin than to make the consumer's life and easier. I would guess (this is purely off the top of my head) that the number of GM's sold hasn't changed that much... but what has changed is GM's profit margin per model, and thus cost savings allow cost cuts to the consumer which may have increased sales. HTC would have the same problem if they produced 2-3x the number of models they do now.
To me the original article reads more like "cars with four wheels have too many choices... one company needs to make four wheel ones, one needs to make two wheel ones, and one needs to make unicycles". That's the jist I got from it anyhow.
Without googling, I'd say most Android manufacturers have less diversity than GM, or a typical car company. It should also be noted that each car model has about 3 different trim levels, meaning each car company probably has 50 or so combinations at any one point.
That is essentially what the reborn GM has done - it paired down a wide range of models by their brands into just a handful. If the recovery of the company is any indication, consumers responded well to a whittled down set of choices over fragmentation set.