I have to agree with Rom in stating that his role is changing, but I do think it's an enforced change because of our injured players and those we have available.
Ross and him are a boss partnership, and what Ross has is the eye for the imaginative, unpredictable passing (sometimes getting us in trouble it's that unpredictable!)
Without Ross we are so much more predictable. When Kev plays behind the striker as he did on Mon, he wants to just play off Rom in a more conventional strike partnership ie looking for flick ons etc.
Naismith doesn't offer too much creativity, and Osman is a fading force. All in all without Barkley are whole system naturally changes, I'm not sure why Rom doesn't understand this rather than voicing annoyance in the press.