[defrost]

> These artifacts exist.

Not according to the original writings, as asserted in the article itself which it appears you did not read.

To quote (the article quoting the Ganguli translation of the Mahabharata)

    The fact was duly reported to the king. In great distress of mind, the king (Ugrasena) caused that iron bolt to be reduced into fine powder. 

Paraphrased as:

    Note that the supposed “bomb” is actually a bolt (like a scepter), that the king feared the bolt, and the king destroyed it before it could be used.

[DropInIn]

And to note context for the King, in the bronze age iron was essentially magic in how it could defeat the standard arms of the time....

Theres a reason the iron age comes after the bronze age, afterall...