Joseph, it depends on what one means by “the world”. There is a midrash that says that Hashem created and destroyed worlds before this. The Torah also says that Adam’s body was created and only later did he receive a “living soul” (according to Onkelos the power of speech.In fact, according to archaeological evidence writing has only been in existence for a little over 5,000 years so perhaps 5,776 is from the time people were raised above the animals. this si the world as we know it.
As for Rav Eliashiv, with all due respect there are other poskim. Perhaps the “halacha” (I find it difficult to write that about a non-legal matter) is not like him.