- and you only need one truthful person to alert you to what’s going on.
That is completely, and utterly, false. Most SPV wallets have absolutely no comprehension of anything but “Header, merkleroot, my thing is in the merkle root.” They have absolutely no way to tell which fork is genuine, to tell whether the subsidy has been inflated, whether the coin supply has been inflated, whether a transaction has a legitimate UTXO it is referencing. SPV wallets understand _none of this_. And even when they are designed more intelligently, they CANNOT do anything to check the coin supply, or validate a UTXO. There is absolutely no physical way whatsoever for a fullnode to prove to an SPV node that it is telling the truth. All it can do is say “I’m saying something different than that other node.”