There are PLENTY of treatments being sold. Many just for money. en.wikipedia.org/wiki/Management_of_hair_loss
Why is it so obvious to outsiders that the three you mentioned are the best ones with the least hassle. Seems like every one of them involves taking them indefinitely, side effects like erectile dysfunction are somewhat common, and if you quit, supposedly, your hair loss would accelerate and it'd be like you never used them.
You write that «there's nothing else» besides those three you mentioned, but Minoxidil is something else that has an effect. At least on me. I used Minoxidil some years back when I was losing hair rapidly, but I was told it was just a telogen phase, so I quit. But it was REALLY easy to see that it boosted hair growth, although only sprayed on the hair, the eyebrows grew hairy and out of line, I got a thin layer of hair on the forehead an inch from the hairline, where it's not supposed to be (had to shave it), even the beard grew thicker and out of its area, an inch higher than before.
The reason I posted was that I saw a headline in the news way back about someone making a living selling remedies agaist hairloss otc (perhaps a shampoo, not sure) and instead of asking about one specific thing, I'd rather ask a general question about what options there are with the least hassle, that's still somewhat effective.