Too much prosperity in too little time sometimes ends up with this sort of thinking.
Besides, in future we will never get a better opportunity than tagging with Russian companies in arms designing than ever. Scientific development is never stagnant; it keeps evolving and ideas keep coming. If USSR had not collapsed, Russia would be still on par with US in everything and it won't have been so easy.
It is still a marvel that Russia rose from the ashes and re-asserted its position around the world. All courtesy the iron-strong policy of Vladimir Putin. India could seriously do with a leader like him.
Barring all the emotional thinking and friendly ties, even from business perspective, as well as scientific advancement, India only stands to gain from future JVs and co-designing and developing. We must remember that world is not running short of countries to say that Russian arms industry is in decline. It is amusing how Western speculations turn so fast when Russia's got this year $ 10 billion in foreign sales---its highest to date (courtesy Rosoboronexport).
Earlier in 90s, there was a concept that once China veers away as self reliant, Russian industry would fall. This was filled with India topping the list of arms client followed by Venezuela, Vietnam, Malaysia (who dumped SH for MKMs!), Indonesia, African nations like Algeria, Tunisia, Nigeria, Namibia and even attract other Southeast and Latin American countries.
For India, this is a golden opportunity to not just help ourselves but help our friends. A win-win situation. And now considering 60 years of relations, I'd like to add something that is very prominent about those who make relations with India:
"We will never forget our friends who helped us when no one was willing to even stand beside us."