LD50 for a human of 70kg is 210g (3g salt per kg of human), so it seems rather unlikely that it will be lethal short-term (though always possible). It mostly becomes lethal when you don’t have any water that’s actually hydrating.
I think you may be thinking of the LD50 for rats. People have died from much less than 3g/kg.
The lethal dose was estimated to be less than 10 g of sodium (<5 teaspoons of salt) in two children, and less than 25 g sodium in four adults (<4 tablespoons of salt).
An acute toxicity from excess sodium intake with the possibility of fatal outcome has been reported in relation to the ingestion of huge amounts of sodium, such as 0.5–1 g of salt/kg body weight.
LD50 for a human of 70kg is 210g (3g salt per kg of human), so it seems rather unlikely that it will be lethal short-term (though always possible). It mostly becomes lethal when you don’t have any water that’s actually hydrating.
I think you may be thinking of the LD50 for rats. People have died from much less than 3g/kg.
https://pmc.ncbi.nlm.nih.gov/articles/PMC5537768/
https://pmc.ncbi.nlm.nih.gov/articles/PMC3951800/