What is meant by the Prophet, may Allah’s prayers and peace be upon him, saying: "For indeed, the people will increase, and the Ansar will decrease," as ورد in the hadith narrated by Al-Bukhari in the Book of the Virtues of the Ansar?

Al-Hafiz Ibn Hajar, in "Fath al-Bari," explained the phrase "and indeed people will multiply and decrease" to mean that the Ansar will decrease in number compared to those who will embrace Islam from the Arab tribes and non-Arabs, even if they multiply, they will always be few compared to others. It is also possible that the Prophet, peace be upon him, knew that they would decrease absolutely, and indeed it was so. As for his saying: "until they are like salt in food," what is meant by it is scarcity, because salt is a small part relative to the beauty of the food.