Gross misunderstanding of the threat model.

Phishing is not the problem here. Your laptop isn’t getting SIPR emails with links to fake login screens.

I think you’re misunderstanding the threat model for why security clearance cares about impaired judgment of your off time, too. There’s more to these people’s lives than when they’re on the clock (figuratively speaking). Getting compromised anywhere is a problem.

Being drunk at the bar/club/social event and telling that very interested lady a bit too much is probably the better example

Still not as bad as being susceptible to blackmail or bribes