Bearing in mind only 45 minutes or so of 24 hours is broadcast per show, and within that 45 minutes, some of it is taken up by Ant & Dec talking, the constant reminders to vote, the trial and the Dingo-Dollar-Challenge, so if you're not selected for either of those, there's very little air-time available. And if some people in there are more entertaining then you'll not really appear on screen.
The real test is when the numbers reduce. If Tinchy is still quiet then fair enough, but at the moment maybe he's just less interesting/entertaining than the others rather than being very quiet.