Though three trains operational from Guntur & Secunderabad, they are being operated in two different routes serving various enroute places.
Places connected with Golconda/Intercity Express are having population of 95,37,561
Places connected with Palnadu Express are having population of 78,44,135
Places...
more... connected with Thungabhadra/Hundri Express are having population of 75,10,645
Places connected with Kurnool-Vijayawada (Special) Express are having population of 27,08,840
As per above, you may have your own calculations regarding proportionate and all, rather than jumping to your own conclusions and judging the requirement as per your assumptions.
Before making baseless comments stating politics etc., please share proofs regarding the politics involved in this.