No it isn't. CA will still try to tax those shares if and when he decides to liquidate them. However, Musk does not ever need to liquidate any shares. If he never wants to pay any tax, all he has to do is buy a hedge against the shares (thereby locking in a particular price) and take out loans against the now hedged asset. And like magic, he's got all the cash he could ever need and zero capital gains.
His estate pays them back when he dies. Inherited shares have their cost basis reset to the current value, so if his heirs sell them immediately there's no capital gains to be taxed.
