The US Embassies in the Netherlands explicitely disallow you from bringing most electronics* and they say they are unable to store things for you.

https://nl.usembassy.gov/embassy-consulates/amsterdam/access...

*It used to be no electronics, but now you are apparently allowed to bring a mobile phone provided you turn off Bluetooth.

The USA consulate in Rio de Janeiro is also like that. Of course, it's become a business opportunity: right next to the queue outside the consulate, there are several people who offer to store your electronics, for a price.

Contrast with for instance the Germany and France consulates a few blocks over (they're in a single building), where as far as I know no such rule exists.

The US Embassy in Paris did refuse to let me in with my laptop. I had to run everywhere to find a place that accepted to keep my laptop for me :/ you definitely get a reality check as soon as you enter the Visa process with the US.

Now I'm curious. Does anyone know why they ask you to switch off Bluetooth specifically (and nothing else)?

in France you have to turn off your phone, then handle it to them. I couldn't turn off mine (it was badly broken xD) so I just took the luminosity to the lowest and they didn't see anything.

Same for the German embassy in France, the phones are asked and kept by the security at the entry.