Aside from the G4 the others all have more and/or faster updates, slimmer software and I'm not going to consider the 808 an inferior processor. These phones are all very competitive with each other so there's definitely something for (just about) everyone in a relatively low price margin here, but of those 5 devices, I think that the TURBO 2 is (for my purposes) the 4th or 5th best (LG G4 is 4th or 5th to me) yet it is the most expensive by a huge amount. I'm trying hard not to put the TURBO 2 (or Moto X Force) too far behind the X Style because the specs are right up there and it even has some perks like wireless charging. I like that you're comparing similar storage models to each other - but right now too many people buy whatever the cheapest option is, so those 16GB devices are going to move volume.
Also keep in mind, my rough top ten list (for my needs) = Nexus 6p, Moto XPE, Galaxy Note 5, Nexus 5x, Sony Xperia Z5, Moto X Play, LG G4, DROID Turbo 2, Nexus 6, HTC M9. So with the Turbo in 8th place, the way my mind works, is that the Turbo should be approximately the 8th most expensive in order to bring its value proposition up to par. That said, the 6P being the current king of phones at a super low price does throw that theory for a bit of a loop.
I think maybe we're looking at this from two different perspectives. I'm talking about what the market will bear, and general cost per specs, and it feels like you're talking about how it would need to be priced to get *you* to consider buying it.
A lot of the things we have to consider when buying are subjective (what's the value of fast updates? what's the value of wireless charging?). For one buyer, a feature, spec, or characteristic may be a deal breaker. For example, the Droid Maxx early on didn't support the Square payment reader. As a small business owner using Square, I couldn't justify buying a phone that didn't support square. The specs and price could be worlds better than anything else on the market, but if it doesn't meet the owners needs (or very strong wants), it doesn't matter. One person may be willing to pay an extra $100 for something like wireless charging. Another buyer won't use it, couldn't care less, and doesn't way to pay one penny extra. As we've seen in this forum, some care about small styling details (like logo placement), while others couldn't care less.
It sounds like you de-value the phone a fair amount for the perceived likelihood of slow & fewer updates (which I agree is likely, and very fair to consider). You de-value it further for its bloatware (though I think to be fair, most or all of the bloatware can be disabled or removed, but it's still there & fair to consider.)
It also sounds like you don't add much value for the shatterproof screen. I'm guessing you have a history of taking good care of your phones, so it's not a major concern (same goes for me, though it would be a little comforting). I'd bet money that if Apple made shatterproof versions of the iPhone and charged an extra $200 for them, they'd sell like hotcakes. For a lot of people, that's a feature that is very valuable, and could alone justify the price difference between the Turbo2 and other offerings.
I can totally understand your reasons for the Turbo2 being down a little bit on your list. I'm just not convinced that your reasons translate into "it would make the most business sense for Motorola/Verizon to price the Turbo2 substantially lower." I think they'll have great sales as-is. I wouldn't be surprised if there were a small drop in price after the new year, or sometime when a new competitor launches, but I think (especially with the trade-in offers, etc) that they'll sell fine for now without a price drop.