Yes, if I understand the studies and the book correctly, a lot of the book talks about how the body regulates sodium, and it has a lot of mechanisms for doing so. The body can conserve sodium, however the longer and the more it has to do so the more the conservation mechanisms create serious problems of their own. And like water and protein for example, the body can conserve sodium but it can't make it. I am now fairly confident that back in the 90's when I thought salt should be minimized, I was putting myself at fairly major risk playing basketball outside in the heat, to cite just one activity. Thankfully I ate a lot of pasta at the time which likely gave me enough to scrape by, but I wish I had known I was taking a severe and totally unnecessary risk.
The book also dismantles the "has been linked to" assertions that there is something about high salt meaningfully contributing to metabolic syndrome. Even if it did so in some small way, the things we already can be confident cause metabolic syndrome (seed oils, excess sugar and carbs, chronically elevated insulin, poor sleep, thyroid issues, lack of activity, poor micronutrient status, etc. ) would certainly overwhelm it as an issue.
I suggest people read the book as it does all of this far more justice than I can.
BTW, unlike Bigtex, I have no idea how much sodium I get. I eat no processed foods so I just try to make sure I don't get too little by adding it to my coffee and pre-workout, especially on sauna days or days when I am doing heavy work outdoors.