I read that quote regularly. Any clue who it originates from? I think it’s a romantic overstatement and does not hold as a general pasta rule. Salty pasta water is needed when you use a sauce or a pesto that has little salt in it. However, when using a particularly salty sauce or pesto, your end result can easily turn out too salty, if you put too much salt in the pasta water. When I make japanese miso-butter pasta for example, I don’t put any salt in the boiling water, because combined with the miso-butter, that would make the end result way too salty.