476 skilled migration visa - cancellation if not entered by IED date?

Sir my name is devansh rai. I am currently holder of 476 skilled migration visa for australia. Sir, according to news australia is not opening its border till late 2021.i got my grant on 20 jan 2020 and had ied of 10 december 2020. But keeping in mind about cocid 19 i requested for first extension and i was granted new ied in june 2021, and validity remained same which is 21 july 2021. Sir, in document it is clearly written that u cannot extent your validity and ied. And if u are not able to travel in valid visa date ur visa will get cancelled.
Sir how can this be possible first they are not extending our validity , second they are not opening there borders and then straight upto cancellation.

Sir if australia choose to remain close till late 2021 , our visa automatically get cancelled.
I waited 3 years for this visa. Now under new budget they are directing authority to refund application charges.
I need a serious help

You should be able to enter after IED date if you can’t travel due to travel restrictions.