He is correct.
That’s why Russia will fight existential war to keep it.
It may be an existential war for Putin, though, seeing as he was the guy who started it.
It’s the naval base at Sevastopol that makes Crimea important.
The breakdown in negotiations of the Russian’s use of the base is what led to the 2014 invasion.
The construction of the Kerch Strait Bridge verifies the importance.
Not much is being said about the Ukrainian forces on the Kilburn Split which controls access to the estuary of the Bug and Dnieper Rivers.
There’s a dearth of news about the military action except the Ukrainian MOD has confirmed they have forces on the splt.