What of the wellbeing and interests of the vulnerable who stumble onto /b/ ill-equipped for the firehose? Are we their keepers also?

This may be one of those "not everyone gets to win everywhere" situations. And if I have to choose protecting 4chan vs. protecting children...

... I can see two positions on the topic which have merit. So it's a good thing there are separate nations to decide on different bars of safety.

I would have no problem with a world where 4chan is free to operate in the US and blocked in the UK. Different countries with different cultures.