If you know why Java is installed on your PC, then you keep it. If you don't know why it's installed on your PC, then uninstall it. Worst case scenario you have to reinstall it when you need it again.
Doesn't make people stupid or stubborn to uninstall unnecessary software that is a potential liability. Not everyone has the time or desire to be an IT wizard or internet security expert. Some people are busy being doctors, parents, engineers, carpenters...