This train is not so unpopular as a whole because :
1. According to statistics of recent few years, generally, a Shatabdi may have minimum 1 EC & 6 CC coaches (ICF Type) (incresing number of coachs within few months or withrawn train is not taken). If a Shatabdi has about same number of passengers through out the journey, it may have 1 EC + 5 CC (old days of 12027/12028), if number of passengers is decreased then it must be have more coaches. This Puri HWH Shatabdi has 1 EC & 11 CC ICF Coaches. So, sometimes vacant seats & lesser time WL in this train don't mean that it is unpopular. If it has only 6 CC instead of 11...
more... then how many seats will be vacant in CC in average? Your maximum demand may be decreasing of number of coaches though extra coach must be attached sometimes if number of coaches are decreased. You can't demand that it must be withdrawn.
2. Average no of passenger is not bad as a Shatabdi type train. Number of passenger is more important than that of vacant seats because expenditure behind an engine + expenditure other than engine & attaching an extra coach is many times (40-50?) more than the expenditure behind a coach. So, extra vacant seats because of attaching more coaches don't mean that it is unpopular.
3. Moreover, this train has about highest number of passengers of a journey in its long part of respective journey - it is 409 kms between Cuttack Howrah. It is lower in 28 kms Bhubaneswar Cuttack and very low in very short route of Puri Bhubaneswar 63 kms. Many passengers for a long part helps to get good revenue.
4. Few people don't know about conversion of Shatbdi from Duronto. So number of passengers will be increased slightly for them.
5 It is better than 12035/12036 JP AF SHATABDI, 12385/12386 HWH DHN AC DD, 12847/12848 DGHA DURONTO etc (3rd is the best among them). If JP AF SHATABDI has 1 EC + 10 LHB CC (about same capacity of 11 ICF CC) (capacity same/ about same as Puri Shatbdi) instead of 1 EC + 6 CC (LHB) then how much will be the average number of vacant seats? If Digha Duronto has 11 CC + 1 EC like Puri Shatbdi instead of 7 CC + 1 EC then how much will be the number of vacant seats in CC in average?
6. Number of the passengers is inconsistent - sometimes high, sometimes low. We have to see the average