yeah, it's like, day by day words die. They gets used less then usual,they get forgetten, they get replaced by other words. This happens to all languages.

It's sort of related to this, Quran is more than 1400 years old,it's fortunate that some words would die/lose their meaning.

It's like(but not exactly) there is more than 500k words in English but not every English speaker knows them.