It is certainly much sweeter than vege/marmite, and I am not sure the remainig taste could be classified as umami. But it has a very distinctive taste.
And, if I am completely wrong, at least I can claim that the consistency and color is similar to vege/marmite.
It’s basically solid whey that’s gone through a Maillard reaction to make a sweet, salty cheese like stuff.
We made some a few years back, but couldn’t get it to turn out as aell as the commercial stuff.
If I remember correctly the trick was in the stirring. Either not stir at all (with the risk of burning), or stir all the time to keep it from crystalizing.
Edit: and yes geitost is the goat-whey version.
I wonder if the shock value is derived from an expectation of chocolatey sweetness. If you’re expecting Nutella, Vegemite is guaranteed to disappoint.