It's precisely as an iOS developer why I'm looking at it this way. A product's next release version may need 100 very simple tweaks/features in. But turns out we only have time for 60 for this release, and having to push 40 of them to the next sprint. Producers and stakeholders meets, discuss this, and have to make a decision. One of these missing simple feature may irritate greatly some of the customers, but the stakeholders had to make the call.
The lack of a BT keyboard may be a HUGE deal for you, but it's entirely possible that there's so few people using one, that the stakeholders decided it could wait for the next release.
Like I mentioned in my post it is possible, and I would add for sake of clarity, very probable, that they don't want a BT keyboard support on purpose. The reason? I can't think of one. I wish I had an ear at Apple's engineering meeting rooms.
All I'm saying is, until they make an official comment about it, as a programmer myself, I see it as potentially the kind of
feature-bumped-to-next-sprint I had/have to deal with every single day for the last 25 years.