Q. Why do currently active religions like Judaism and Christianity not give a specific name for, but refer to descriptions of God generically? Current Islam seems to have assigned the name of Allah. Current Hindu gods have names. Expired religions seem always to have used names for gods and god-men.
Because Judaism and Christianity are monotheistic, in general they do not use a proper name for God, since God does not need to be distinguished by name from other divine beings, which these religions do not believe to exist.
However, there actually is a proper name for God in the Hebrew Bible. When God sent Moses to Egypt to deliver the ancient Israelites from slavery there, Moses asked God, “Suppose I go to the Israelites and say to them, ‘The God of your fathers has sent me to you,’ and they ask me, ‘What is his name?’ Then what shall I tell them?” God gave a very interesting answer to this question, saying in Hebrew, ‘ehyeh asher ‘ehyeh, or “I am who I am,” and then telling Moses to say to the Israelites: “‘Ehyeh has sent me to you.”
This may not actually have been the disclosure of a proper name at all, but the claim to be the only God who truly existed, i.e. “I am who I am, and all those other so-called gods are not.” But Moses took the phrase “I am,” expressed in the third person as “he is,” since Moses was speaking about God rather than as God, and used it as a proper name for God, Yahweh. This usage is found throughout the books of Moses or Pentateuch, as well as the rest of the Hebrew Bible, so that this name actually occurs thousands of times there.
However, in order not to violate one of the Ten Commandments, the one that said not to take this name in vain, Jews completely avoided saying it out loud. When reading aloud from the Scriptures, they would substitute the expression Adonai, “the Lord.” When vowel points were added to the consonants in the written text of the Hebrew Bible, the vowels for Adonai were put with the letters YHWH, and when the Scriptures were translated into other languages, the expression “the Lord” was used in place of the proper name. Greek translations of the Bible used the term kurios or “Lord,” and this usage is reflected in the New Testament. That is, when the New Testament quotes the Old Testament, it says “the Lord” where the Old Testament says Yahweh. As a rule, English Bibles follow this same practice. They say “the Lord” wherever the name Yahweh appears, although many of them put the word “Lord” in small caps to show that it represents the name..
That is how we get the impression that Judaism and Christianity do not have a proper name for God. They do. It is actually found throughout their Scriptures. But they tend not to use it, both as an affirmation of monotheism and as a way of showing respect for the name of God.
Ancient religions, by contrast, did tend to use proper names for specific gods because they felt they had to distinguish them from other divine beings. The same would apply to Hinduism, which is a polytheistic religion. Islam, for its part, is monotheistic, but I think you are correct that the name for God in Islam, Allah, should be understood as a proper name. It actually means “the God” in Arabic, but it is treated as a name. However, I do not think that this takes anything away from the strong commitment to monotheism within Islam. After all, the basic statement of faith, the first of the five pillars of Islam, is, “There is no God but Allah, and Muhammad is his messenger.” So while I am not an expert on Islam, I do believe that Muslims would say that the one true God has self-revealed to humans under this name.
Good Question 
I believe it’s important to use God’s name. Yahweh, or the English translation of that name Jehovah allows us to have a personal relationship with Him.
Romans 10:13 says, “For everyone who calls on the name of Jehovah will be saved.”