Why do Browsers implement a Same-Origin-Policy (SOP) to prevent open websites in the browser from executing scripts that may access / modify data of other open websites in the used browser?
Another more 'usual' approach would be to simply sandbox each open website, i.e. every website 'thinks' to be the only website on the browser. This approach is in my opinion more familiar to prevent an attack of e.g. evil.com accessing data from bank.com.
Is there any advantage in using SOP with respect to sandboxing?