>In almost every other field
Phones are not designed to be a specialized tool of a field. They are gadgets designed for a general audience of billions of people.
>For some reason, technology has ended up different
Because with computers there is a lot of freedom in how things can be made to work without adding extra cost to the product. They can be designed to be user friendly.
Cars, knifes, power tools, and a million other things are also designed for a general audience of billions of people. And if you do not learn or use these responsibly you'll end up with a lot worse outcomes than getting some malware on your phone.