Why is there a fundamental difference in these? 'Legitimacy' is a cultural conceit as arbitrary as any dogma- you just appear to like it more. Nor is there any inherent relationship between the sincerity of a closely-held cultural site and the distance involved.
If you don't want to be compared to the sort of archeologist who would break into the Yucca mountain nuclear waste repository out of ignorance, it would behoove you to lay out an intellectual framework about why you wouldn't break into the Yucca mountain nuclear waste repository out of ignorance. 'Legitimate ownership' doesn't cut it, not least because the point of the repository is a no-ownership scenario, nor does 'I would take great pains not to destroy anything' when accessing the knowlege within requires the destruction of the containment.
It doesn't help that you've so far set out a no-win scenario for any sort of 'legitimate' restriction authority. If it's a god who says so, it's an unjust and immoral, illegitimate restriction and should be strived to be overturn. If it's not a god but merely deemed a god (er, yeah, something like that), then it's illegitimate and should be overturned. If it's a bunch of people, they have no right to do so and so are illegitimate and should be overturned.
After the last few years I've yet to see you lay out any 'legitimate' authority to forbid you from breaking open a secret. The only 'legitimate' restrictions I can ever recall you claiming to respect are just as arbitrary and culturally dependent as the dogma you vocally reject. That's far from a convincing distinction from someone who has in the past excused acting out of ignorance in the name of acting out of ignorance.
You're using a lot of awfully loaded words here. Let's cut through the rhetoric, shall we:
I. The Basics
First and foremost, what I actually do claim can only imperfectly be translated into a breaking-and-entering metaphor. Let's phrase this carefully:
I do not accept any authority to enforce an injunction that I may not inquire into certain areas of knowledge.
Now, the Maker in the story of the Golden City symbolically represents such authority, but the fact that it's presented as a breaking-and-entering metaphor is already part of the propaganda because it gives the attempt to enter an aura of illegitimacy before the real question is even addressed. In fact, since I do respect others' life and property, my refusal to accept such authority does not automatically translate into "I will break into your house to see the skeletons in your closet". What I'm prepared to do to circumvent attempted restrictions is still limited by ethical concerns, questions of risk vs. benefit and political concerns. I'll address those next.
II. Risk and Ignorance
You also attempt to discredit my arguments by claiming that the actions resulting from my philosophy are made in ignorance. Here's my answer to that:
If we act to acquire a piece of knowledge, we naturally and by definition act from a position of ignorance. Is that ignorance bad? Yes of course it is, that's why we act to change it. If you claim that this ignorance should be reason enough not to act, then you ultimately invalidate any kind of empirical knowledge acquisition. Any exploration and experimentation carries a risk because it is the point and the rationale that we do not already know the results. By saying that we should not explore and experiment because this may result in disaster you also invalidate any kind of empirical knowledge acquisition. Basically, any fundamental injunction based on this rationale ends with "We are forbidden to acquire any knowledge we do not already have".
Now, you may ask where is the point where reason and consideration for large-scale wellbeing and survival limits experimentation and exploration? There is really no hard answer to that. All we can do is to be as careful as we can, honestly evaluate the risks to the best of our ability and if need be, defer further exploration to the future, but there will never be a guarantee that we won't cause a disaster with the next tiny step into the unknown. If we are not prepared to accept that remaining risk, we will stay forever as ignorant as we are now. Some ideologies claim that we should, indeed, stay as ignorant as we are now. Like any claim about what should be, neither they nor those that oppose them can claim fundamental objectivity. Which is why this is, unfortunately, ultimately a political matter decided by which ideology has the greater memetic power. I would prefer that we do not forever stay children.
III. Cultural standards and politics
Lastly, the supposed problem of cultural standards is not a problem in the way you claim it is. All our ideas of authority, property, rights and legitimacy are dependent on culture, but what else do we have to argue from? If we dispense with them, we are left with a might makes right scenario. At the same time, I cannot be expected to accept any claim of ownership made in the name of an ideology because I can't reasonably be expected to give others unlimited authority over my actions. If some culture throws me out of their territory because I violated some silly - from my POV - taboo, they have that right. It's their territory. According to both our cultural standards, most likely. But don't tell me you would readily accept an injunction to, say, not capture and analyze the light of a star 10kpc away because some culture considers it the home of their god. Yes, cultural standards determine what we're willing to accept, but we have nothing else. The only two alternatives would be to either accept no limitations at all and indiscriminately bulldoze over cultures less powerful than my own, or accept any arbitrary limitation by the crackpot ideology of the day. Since there is no philosophically solid foundation to stand on, in practice such things are most often decided by politics, which may sometimes end in using force. In any specific case, my decision about what to do, whether to break open something in a non-ownership scenario, would be decided by pragmatism. Non-ownership does indeed mean that I don't accept any authority to enforce an injunction, but that doesn't mean I need to be reckless or needlessly offensive about it. There is no hard answer. There may be various pragmatic reasons to back off. The question of risk and ignorance is covered by the previous section.