You realise that your ISP knows exactly what porn or disident material you're reading, right? Unless you're one of the few people who use privacy methods).
It's quite a difference between saying 'I like hardcore porn' and watching it. While the ISP might certainly create a profile about you that lists you as a porn lover, that's a lot harder (for example: You might go for lesser known/_unfiltered_ porn sites anyway or tell them that you want porn because you don't understand the filter and assume that all your torrents with new 'material' won't be available otherwise).
I agree with your general point, but I don't think these things should be conflated. Having to state one's stance towards any kind of content is different from someone watching over your shoulder.
Opting out of the filter is not saying "i like hard ore porn", it is saying "i want to read sites like HN that are wrongly blocked by your shitty filters".
Please take a look at the screenshot posted elsewhere. BT at least seems to offer you ways to do exactly that: Stating that you like porn (one category), nudity (another), alcohol/tobacco (third) or 'tasteless' content. There are more categories, but these are quite .. interesting.
Sure, you _can_ opt out completely (not sure if that means that the BT site lists you as looking for all of that though, which might scare users again: "What, no I don't need tasteless material!").
Still, the UI leads you to state what you want (custom) or some predefined presets for all I can tell. That IS close enough to saying 'I like porn'.
I don't argue that
- disabling the filter might have other/better reasons than mature content
- filtering is broken, stupid, idiotic and will never work correctly - and opting out for that reason alone is a good idea
Yes, that's how it reads to anyone in the know, but how does it read to the general public? To you future employers? To your electorate, should you ever run for office?
You're basically saying that you're happy for someone to collect information that -- at least in prudish Britain -- could be easily used against you. I'm amazed that so many HN users seem fine with this, given the normal outcry when Google wants to gather something as trivial as your geo-location.