The only coins proven not to be spendable are the 50 BTC rewarded for the Genesis block (block 0)
I think he meant the Genesys block, yes. Some call it block 0 while others call it block 1, as it is actually the first mined block.
That would have made sense if the linked blocks 2,3,4 where actually for 1,2,3. In that case he just would have started counting from 1 instead of 0. But that is not the case. Just check the links yourself where block 1 (so not the genesis block) is skipped: