To you maybe.
But the reality is that I am doing work on my iPad, without desktop OS, desktop apps, a keyboard or mouse.
As mentioned, I teach with my iPad in class. I annotate on pdfs in Notability. I PDF Office to scan, create and edit PDF documents. I record screencasts with educreations. I create documents on iWork's, using only the on-screen keyboard and the touch interface. I update my class blog using the wordpress app. All these feel more seamless on my iPad because of the app nature (it's actually faster for me to take a photo using my iPad's camera, then insert it directly into a document or blog, for instance).
The iPad also got another boost in productivity with extensions on ios8. Now, I can crop photos directly, annotate on them etc, all with extensions in the photos app. Save articles directly from Safari to Evernote or Pinboard. Create calendar events directly through Fantastical's share sheet extension. The possibilities are endless!
Outside of work, it's also my entertainment device, which I use to listen to podcasts, music, light gaming, youtube, and news reading.
This may not constitute "real work" to you, but it's work for me.
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And my point is - so?
It is precisely because the iPad lacked a keyboard and mouse that allowed it to evolve into the modern day tablet it is today.
Are there people clamouring for the ability to be able to do this sort of complicated work on a tablet, when they could be doing so on a laptop or a desktop PC with a 27" monitor? Not everyone sits behind a computer terminal and handles tons of data everyday.