> The problem is that windows was developed before security was important.

I disagree. Plenty of systems have added security as an afterthought and were just fine for the effort.

The problem is most people just want to play video games. They don't care about security. They don't actually want security if it frustrates their efforts to play games or reduces the computing power available for the game.

Look at houses. We could have amazing high security locks everywhere if we wanted. We don't. We don't perceive ourselves as needing them. It turns out "tamper evident" is a decent level of security for the real world and allows homes to be partially secure while being totally livable.