Is Crimea Really Defensible?

If Russia’s land bridge to Crimea is cut, i.e. Ukraine’s army reaches the Sea of Azov, is the peninsula even militarily defensible against modern NATO weapons? Even from current positions, the Kerch Strait bridge is just in range of Storm Shadow cruise missiles. From any position on the Azov coast the bridge is a sitting duck, I wouldn’t expect it to last a week once Ukraine commences attacking it in earnest. The Sebastopol Naval Base, which is already threatened, would have to be abandoned too, which the Russian navy has partly done already. Without the bridge, all supplies have to come in by ship, under fire by drones and missiles. Putting aside ammunition, will the Russians be able to replace armor and artillery as it is systematically destroyed by precision artillery and missile attacks? Doubtless most civilians will flee. For one thing, the water will be cut off, and Crimea is mostly semi-arid. Finally, in a sense the narrow neck puts the Russian army at a disadvantage, because they must concentrate all their forces in a small area that will attract incredibly dense artillery attacks.

I’m curious what our Kossack military experts think?