No one knew how much the patent was worth until Xiaomi was banned in India

Hello, the value of a patent has nothing to do with what you said.

What you are talking about is the exclusive right to use a patent. That is to say, even if the patent is of little use and is only worth a few cents, you cannot use it if I do not authorize you to use it.

This is a strategy or method for patent protection and has nothing to do with the specific value of the patent.