Because the people do not bother searching for what's out there for offer? They simply do not care about diverting from the well trodden path. Brands and dealers pay YouTube reviewers who shill for them and viewers blindly go for them based on someone's recommendation. This is literally why the entire market is flooded with Chinese stuff (especially for headphones and earphones, in that industry the fate of a product almost entirely depends on a reviewers' judgement, because the audience are blind followers of them) and due to this the lesser known brands are kept in the dark, as they don't have the budget to pay off dealers and reviewers or market their stuff aggressively. I'm not saying every mainstream brand is bad and only Indian brands are good. It's just that many of the people base their judgement on reviews instead of exploring other brands and routes themselves and going out to actually hear what is on offer. If one discovers a hidden gem and tells us, it benefits everyone.
I dont think you have answered @keith_correa query. The onus is on the manufacturer to increase awareness. Consumers buy what they feel is the right choice and will continue to be happy with the purchase but its the manufacturer who is losing a potential market share by not increasing awareness.
The other issue is size and risk. How many would buy equipment from a one person brand ( indian or otherwise) when you have a concern that if the brand closes down you are left high and dry hence the interest in a bigger brand which has less risk.
The other end of the spectrum is chinese..which is so cheap that you would not think twice if it fails
Of course all of us do have a vested interest that indian manufacturers do succeed. 2 brands which I know are there in quality are Rethm and Acoustic portrait. Lyrita makes wonderful products and a lower price range as great VFM as well. No idea of others as have not really personally experienced them but am sure from the talk they are good..they just need more visibility. very often being around for some time also helps.
Hope they come up..the market is there I am sure