Hyde Act is a domestic law of the US as a domestic law cannot bind us as a sovereign country.
It is not even mentioned under the 123 or IAEA Agreements except indirectly that nothing in the 123 Agreement will render its implementation contrary to each parties prevailing national laws.
So technically, the Hyde Act has to be followed by the US if they supply us nuclear plants, spares or fuel.
Here is the catch. While the Hyde binds the US as a nuclear supply, being a domestic Act it has no jurisdiction in India. We are only binded to our national law and what we commit in the 123 Agreement.
So in case of a dispute, legally there is nothing the US can do to make us binded to the provisions of the Hyde Act.
Secondly, countries like France, Russia etc do not have such Acts. This makes the US the least favored supplier. If the US nuclear suppliers want to trade with India on a competitive basis, they will put pressure on the US government to pass an amendment to give India a waiver
