What you said is true
Atlas are part of erstwhile group like C K birla, Videocon, BPL, Premier, Onida etc. were thrived in License raj but when Liberalization hits folded and becomes fringe players with each of them going on crisis in different years.
Second range consists of Micromax, Lava, XOLO, Karbonn, Celkon, Intex, Spice, Smartron, Vu etc. All these guys are more or less resellers selling ODM Products as their with no control in quality of products. Resulted in complete annihilation in Indian market. Today Micromax and Lava are still trying to bring products but still struggling while others are in either bankruptcy or shut their shop.
The third group is current boys like Boat, Noise, Ptron. Survived the Chinese attack by relying on customer support and better marketing. But glaring holes like no production in India, no R&D to show. Future: May face the same fate as smart phone manufacturers if Chinese adapted to it. To survive invest in Indian supply chain and invest in good R&D and also focus to sell products globally.