It makes IP68/69 waterproofing standard difficult to achieve. I suspect that is the main driver.

All of the big companies know that most people aren't willing to base their purchase on whether or not a phone has a headphone jack, and therefore they don't have much to lose from ditching it. They can use that space for more battery or for whatever else they want to put there. The inside of a modern smartphone is a pretty space constrained place.

Buying 6 dongles would also only cost $54 ($9 each) which isn't a ridiculous price for an accessory in my opinion, especially if you're buying a high end phone that's going to cost you $700+ anyways.

Personally, I just carry one dongle attached to my keychain and keep one in the car. It hasn't been an issue for me yet.

As a Nexus owner (4, 5, 6, 7), I am 100% willing to compromise in camera quality. However, something has to give. If this phone debuted at $299 or even $349, I suspect we'd be seeing very different results.

It is a shame too because I think the Amazon Fire phone failed for the very same reason.

In hindsight, the ridiculous invite system that one plus had makes sense now. Maybe they were trying to limit the number of phones sold because each one sold at razor thin profits (possibly at a loss after warranty support).

Downvoted for stating the obvious? $100 bazillion needs to be put in perspective.