But we don't need any government intervention for this kind of thing. You can already maintain such a whitelist yourself, and interest groups can collaborate with businesses interested in maintaining their public image to have a centralized registry of voluntary certification for websites (similar to those ratings for e.g. movies that we already have).
Separately from that, if switching DNS servers is an easy workaround to keep access to porn, kids interested in it will quickly learn how to do so, trading recipes and even downloaded content directly. Ditto with Tor etc.
The fundamental problem here is that it is an attempt to censor something for which there is huge demand among the very group that's being excluded. The only way you can do so that would actually work is full-fledged panopticon, where all communication channels are pervasively monitored.
Separately from that, if switching DNS servers is an easy workaround to keep access to porn, kids interested in it will quickly learn how to do so, trading recipes and even downloaded content directly. Ditto with Tor etc.
The fundamental problem here is that it is an attempt to censor something for which there is huge demand among the very group that's being excluded. The only way you can do so that would actually work is full-fledged panopticon, where all communication channels are pervasively monitored.