My point is that I don't think it's effective to respond to every "slippery slope" by not letting people anywhere near the slope and holding them back from talking about things they care about because they touch the slope. But rather to pick your point on each slope, which gives your people more opportunity to be open and,if it involves company policy etc, for you to get feedback - although the final decision about what the company does of course still rests with you. And if a topic just doesn't work, ban that.

Re the specific example: I'm not from the US, so a fundamental right to guns (or even just much in the way of gun culture) is culturally "weird" here. I didn't intend to suggest that this would be weird/off-limits to all companies everywhere. Which is kind of the point again: find what works for the topic for your people.