That seems very dangerous, and extremely bad public health policy. There are major concerns with anti-biotic resistant bacteria. I came across an article from 2017 suggesting the government clamped down on this. Is it still the case that anti-biotics can be purchased without prescription?
https://www.outsourcing-pharma.com/Article/2017/01/16/Indian...
Also, I'm confused, I can easily buy over the counter Vitamin D supplements in the US. Is the dosage of those not large enough?
One that got me into it was Rogan's interview on the subject (whom as an individual I don't generally looking to a source for health advice, but the person being interviewed seems legit and my after-the-fact research seems to back this up): https://www.youtube.com/watch?v=tBSfIckPV44
So I'm assuming the dosages are too low. But so are most 'natural' supplements.
Edit: this is the HN comment link for OP's mentioned "Shannon's Story" article https://news.ycombinator.com/item?id=24261948
All the bottles at my pharmacy were 1000IU so I just bought one of them and take 5 of them.
I was surprised to read in the article (and elsewhere) that 5000IU doses was mentioned as a common OTC dose as I couldn't find it. But I live in Canada so maybe it's different.
The news article may be right, perhaps they clamped down on it. I am aware of people in the US buying aquarium or livestock antibiotics to treat themselves because healthcare is too expensive and time consuming.
The US is not the rest of the world.