How is it going to have value if the client people download at bitcoin.org don't support the chain with massive hashing power you speak of? Not to mention PoW c

How is it going to have value if the client people download at bitcoin.org don't support the chain with massive hashing power you speak of? Not to mention PoW change. So, no, hashing power is not "all you need" to take over Bitcoin. For many people, Bitcoin is whatever their wallet supports.