^ You are wrong. NASA. used to co-operate with ISRO in 50s with sounding rockets and stuffs like that. But that was a history long time ago. Since then U.S. took keen interest in preventing India from developing cryogenic engines. In 90s, Russia was co-operating with India towards India's aim of developing cryogenic engines. But under U.S. pressure Russia stopped. Not only that ISRO was heavily sanctioned by the U.S. and it allies. The main objective was to prevent India from developing heavy lift rockets. It is remarkable that Indians were able to develop these sophisticated technologies despite heavy sanctions. Even China did not have to undergo such gruesome sanctions as India did. I find it funny that you think ISRO was helped by the West.
They did a good job but you are naive if you think that they got there entirely by themself. As you say the Russians helped them in the 90s. More importantly a French team assisted Nambi Narayanan for almost 2 decades in the building of this rocket hence the similarity with ESAs Ariane.
Also to put this in perspective the Russians and Americans were putting manned missions into space in the 60s. They got there despite Americas attempts to block them doing this when India refused to pay for Americas over priced assistance.
Russia was stopped from helping India. That is the whole point. U.S. did everything it could to stop India from building cryogenic engines. U.S. pressured other countries as well to stop any collaboration with India on cryogenic engines. Yet India succeeded in building this from scratch while under sanctions.
There are some Europeans who grow up with bias and heavy sense of white supremacy. They seem to have hard time coming to terms with the fact that a non-white country can develop things on it's own.
If what you are saying is true and if space technology were truly open source like you are saying then every country would be going to Mars and beyond right now. However, that is not the case and that should tell you that your information is incorrect.