But it isn't the 90s anymore. Billions of people are using the internet, doing everything from voting to shopping to managing their stock portfolio. There are valid reasons why we have security protocols.

And aside from that - it's not like CORS is preventing you from anything. The only requirement is to read up on it, understand it, and configure your web server accordingly. If you're unable to do that, or you'd rather create your own browser, then the only conclusion I can draw is that you're either unwilling or unable to take proper care of the security of your users.