Green tea is usually prepared with 80 °C water. However, I found some variants in a supermarket (they are pretty cheap), where there is 100 °C written on the box. Is it some kind of fraud made by the companies, or there really exist such variants?
I'm no expert in this, but some googling lead me here.
[...] the naturally farmed tea contains much more poly phenols as compared to the ordinary tea. In addition, the tealeaf of naturally farmed tea is not bitter, even if we chew the raw tealeaf we can hardly taste the bitterness. For the naturally farmed tea, it is highly recommended to use boiling water so as to extract more poly phenols. In order to maintain the freshness of the brewed leaf, we can brew tea at higher temperature for a shorter time, such as 100 degree C for 10 seconds instead of brewing at 60-80 degree C for 1 minute, unless you prefer less flavor and thin taste.
Also, there's another product on amazon which mentions the preparation temperature to be 100 °C.
That said, there's another resource, advocating for that 80:80 rule (80 second in 80 °C temperature), but it also mentions:
[...] If you still want to steep at 100 degrees, then just buy a cheap green tea.
Looks like you've just found that variant.