I think that it is to indicate that there are people of one nation (singular) are coming together with the people of another (two singular making a plural) both with equal advantage. However it is correct to say " great days are ahead for the people of our two nations"

When one says 'two people' it means 兩個人。

Hi Cady, "People" is rarely plural. When it is, it a shorter way of saying "more than one type/group of people." More specifically, it refers to more than one demonym of people. In this example, there are two countries and thus two nationalities, so there are two demonyms (two peoples). Here's another example: "Establishing friendlier trade relations between our three cities is a benefit for all three of our peoples." I hope I helped answer your question. Please let me know if I didn't.