It’s probably from the yeast extract which is part of the heme

To be clear tho it still doesn’t have all that much salt. It’s more that raw beef just barely has any. Both impossible meat and raw beef pale in comparison to the salt content of the final burger, where the sodium content skyrockets from things like ketchup, pickles, seasoning the patty during cooking, the salt content of the bun, etc

And imo you should still salt/pepper an impossible patty after formation. As mentioned, while the salt content is higher, it’s still not terribly high, and imo it benefits from a bit more. In my experience it’s not like meat and you can salt whenever you want (whereas with beef you generally want to salt patties absolutely last minute to avoid giving the meat a lightly cured texture)

Oh yes it does have enough salt to stand on its own. I never add salt to either Beyond or Impossible brands. I might add other seasoning if I'm trying to hit a flavor profile (liquid smoke, cajun spices, curry, etc).

You can just plop it out as-is and it'll cook up nicely. Just don't squish all the liquid out of it. I've had some nasty versions because people get away with poor cooking skills with reql meat and these don't tolerate the same abuses.