Is the "Language Level Changed" warning dialog still needed?

I just changed the language level of my project and a "Language Level Changed" dialog popped up. This dialog has the following text:
Language level changes will take effect on project reload. Would you like to reload project "<Project Name>" now?

I click No, but now it seems the correct error highlighting for the language level I just selected is done anyway. Is this warning still needed or could it be removed?

Bas