The platform operator can't. That's how common carriers work (telephone, your ISP etc.). But things running on that platform could. Basically look at reddit and perhaps take it up a notch. If the platform operator does not want to be associated with some of the stuff happening on their site then perhaps they should deemphasize their branding. It wouldn't be "reddit/watchpeopledie" just "watchpeopledie".
I not sure how this could work for a single-purpose community like HN. Maybe if YC ran a neutral HNaaS then the HN-prime could be operated and moderated by independent staff.
An alternative approach would be exemptions for non-profit sites.
I think it would be possible to operate within these broad rules if the details are crafted right, but even then it would require significant adjustments for many site operators.
I not sure how this could work for a single-purpose community like HN. Maybe if YC ran a neutral HNaaS then the HN-prime could be operated and moderated by independent staff.
An alternative approach would be exemptions for non-profit sites.
I think it would be possible to operate within these broad rules if the details are crafted right, but even then it would require significant adjustments for many site operators.