For what it's worth at this point, my thoughts on this are that objectivity from the perspective of 3d inhabitants can be nothing but subjective. Sure, we can strive to broaden our understandings and we all benefit from doing so but, if we think for one second this gives us an objective perspective, we're just in a state of ego driven delusion.
As an analogy, science, refuses to acknowledge the presence of anything it can't measure, and on this level, it has to work that way or slide in to the realms of undemonstrable fantasy. However, that means that as time goes on and measuring equipment evolves, what science accepted or denied as being true 5 years ago, is all open for revision in the years to come. This of course means that 'objective science' is only as good as the data it can measure at any particular time, and therefore not objective.
As individuals we suffer a similar fate. we can look back on thoughts and beliefs from when we were teenagers and wonder how on earth we were ever so stupid, yet at the time, the sum of our experience led us to believe that our opinions were indesputable fact. As we have grown older and experienced the realities of life on the 'open road', we have learned that what we saw as indesputable fact, was in fact, total cobblers.
So, given that 3d is inherrently so narrow in its ability to perceive, canwe really sit here and talk of objectivity?
Secondarily, everything I truly understand and can argue anyone in to the ground about, has come about by first hand genuine 3d experience.
If we can genuinely experience objectivity in this realm, what is the point of any other densities?