I don't think that explanation contradicts Pieter Wuille, or me. Nobody is saying that
every transaction on the blockchain will look identical.
What, specifically, do you disagree with in these statements?
Taproot can make all different types of transactions look identical, including simple payments.
What [Taproot] does is make simple payments and multisig transactions and Lightning channels and many more things policy indistinguishable from each other; you won't be able to tell from just blockchain data which is which.