india has a very weird medical economy at times, geared to the costs necessary to deliver ultra-basic care to many people who are dirt-poor, utilizing generics (occasionally of questionable quality), the ultra-cheap cost of labor, etc.

for example centchroman is an interesting case-study... the government basically paid to develop and take it through trials and it was generic from day-1, and then the generics manufacturers go to work and you have birth control that can be delivered to market for under a dollar a month (4 pills) in retail quantities, and the government distributes them free because it's cheaper than pregnancy/social services.

https://en.wikipedia.org/wiki/Ormeloxifene

Not that at the high level, the care isn't great, but, a lot of india is super poor and underdeveloped and delivering core medicines cheaply is relatively effective to provide a super basic level of care, they have a focus on delivering super cheap generics that cover the basic use-cases. I'm sure the glasses are cheap shitty molded plastic or something, or at most a super basic molded glass lens, perhaps with some subsidies. I'm mentally imagining the "BCG" glasses from basic training, designed to be indestructible and unscratchable (aka the birth control glasses).

https://en.wikipedia.org/wiki/GI_glasses

But that is the 80% solution, make em cheap and polish em up with super cheap labor and with basic materials you probably can get that down to 2 bucks or within subsidy distance of that.