Your link doesn't imply that. It suggests that "other" is the category replacing iOS in the market, which are no-name brands. Its not a trend where consumers are paying $450 for a Google product, but one where they're paying $200 for something generic. Amazon and the other players are just holding their ground.
On the Apple side, I know people who bought the larger iPhone no longer felt a need for an iPad. I'm sure the same trend is true for Android, so its unclear who exactly is still buying tablets. Could it be people in markets/demographics where they can't get/afford full-featured phones?
(I personally dislike tablets as a form factor and have both an iPad and Android tablet gathering dust, but people do seem to keep buying Android tablets.)