There probably aren't too many people in the world who enjoy having their views challenged, but anyone who tries to be intellectually honest realizes that doing so is often a painful necessity to maintain that honesty. We can all fall into logical and emotional traps, but pitting your ideas against someone who has different ones can both sharpen your own, and burn away what needs to be left behind. Either way, it's enriching for you.
Explicitly needs to mean enthusiastically gatekept. The issue is squishy righties that like to welcome in moderates and let them rise to leadership roles who let in hard lefties who rise to leadership roles. Be discriminatory, ask hard questions and inspect every answer.
Part of why they passed over the Castile case is because the officer who shot him was Hispanic. Doesn't play into the anti-white narrative.