There is a very big difference between ISRO and DRDO.
While ISRO need to make things (case in point this Scramjet), DRDO need to make things that are better than or equl to western products.
It is the difference between "passing an exam" and "clearing a competition".
no, corrupt politicians sabotaged or tried to sabotage many project. They sabotaged HF 24 Marut. They tried to sabotage tejas, Akash etc. They did not sabotage surface to surface missile as it was not possible to buy them from market and so we developed very much in surface to surface missile.