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Agreed.
Shorting allows a long holder (who wishes to maintain their long holding over the long-term) to hedge against their position over a shorter time frame WITHOUT selling their long holdings and potentially triggering a CGT event &/or resetting the 12-month CGT discount timer.

Buying 'put' oppies could achieve a similar hedging mechanism, but oppies suffer from time decay and transact in the synthetic (oppies) market. Shorting, on the other hand doesn't experience decay and the position is opened/closed in the primary (equities) market.

And that's only talking about pure hedging without considering the possibility that a LT holder might want to take a separate punt to take advantage of some seasonal/cyclic SP weakness, which @Fr3sno has alluded to.

There are many ways to skin the cat in this game. Don't fall into the trap of narrow thinking.