It's interesting that the writer takes it as a given that the government isn't representative of the people and that the majority are to the right of the government.
Of course, if there is a majority for an agreement, the same majority could simply get rid of this law first to avoid a referendum.
You don't even need a majority, a plurality will do. 20 MK can abolish the law tomorrow if they want to. the truth is that this law has a symbolic meaning and not much more, any PM who'll want to to retreat from any part of the state of Israel will just abolish the law in a simple vote, no need for an absolute majority.