Side note, is this what archaeologists use, to figure out the composition of a coin, etc.?
There is the question of trust of the measurement where they will just sell you an approval stamp for 100$.
There is also the problem that some actors have incentives to cheat, like feeding insects to your salmon, and feeding the insects from literal garbage that may get contaminated by electronic components in the dumpster. Or maybe the specific salmon just ate a ball of mercury but was not selected for testing.
A generic tool, that can analyze your immediate environment without having anyone else involved is empowering and can catch a wide variety of problems that you can track further if necessary; feels like a freebie offered by Science. Although it will still need some years of work to make it as sensitive as they show it in Science-Fiction.
Humans have not evolved alongside everything we extracted from the ground since the industrial revolution. It's like a new pair of eyes that would help you avoid a bad apple or smelly fish.
If we could also get a cheap and easy to use Raman spectrometer to complete the XRF analyser it would also be a great addition.
(I don't know what archaeologists use but they definitely can use a XRF analyser to find the composition of coins)