I wonder if dual-SIM phones have the capability of setting call acceptance rules based on a schedule.
There's a lot of things you can't easily buy in the US, but it's not because of some grand conspiracy, it's because American consumers wouldn't buy enough of those things to make it profitable to sell them. PC computers pre-loaded with Linux is one example (it's been tried, multiple times). Another example is "washlet" toilet seats, which almost every toilet in Japan is outfitted with. They were invented in the US, but good luck buying one here, though any appliance store in Japan will have them. They don't sell them in America because almost no one would buy them, because Americans just aren't as hygienic as Japanese.