Last I checked you still can't develop software directly within iOS. So you can't actually develop software for the iPad, on the iPad.
Sure you can remote into another system, but that just makes the iPad a terminal, not a computer.
On my rMBP, and Surface Pro 3, I'm able to run Eclipse and do work when I don't even have an Internet connection. I can compile Java code, and then test it in a local copy of Tomcat. I can't do any of that on my iPad Pro. I can even run a light VM for testing (yeah, even on the Surface.. could use more ram of course).
So I'm sorry but the platform isn't dying. Just as there is a group that can perform their tasks on a limited function tablet, there is a group that needs a real computer to get their work done. You can even go as far as saying that the platform you claim is dying, is needed to keep the platform you see as the future, alive.