The alternative, which is Linux, is to grant your calculator app the permissions to read and write to the same resources that your browser uses to store the password for your bank.

Well "grant" is too strong of a word. "By default and there is nothing you can do about it unless you are exceptionally skilled" is more accurate.

Also your calculator app can read your sudo password as you type it, which you do a dozen times a day to carry out complex and security sensitive tasks such as "Connect to printer to print out mom's recipe for brownies" and "restart bluetooth because it's buggy and you want to listen to spotify on your wireless headphones".