You are correct.

Interestingly, the 10x shares held by Brin and Page constitute only 11% of the economic value of Alphabet, but 51% of the voting control.

And the 10x shares automatically convert to 1x shares upon transfer or inheritance, so if the founders cash out or die, the 10x supervoting power disappears.

Oh wow so that lets them honestly say they have the same value as other shares?