The belief that another society is just as good as yours is lame.
The belief, without sufficient and appropriate evidence, that any other society is just as good as yours is exactly as dangerous as the belief, without sufficient and appropriate evidence, that yours is superior to all others. The former, when it happens, is a mistake that tends to be made by liberals; the latter, by conservatives. The root cause is the same for both, however - baseless assumption.
However, it is only fair to give equal attention, and benefit of doubt, in the process of gathering such evidence as is necessary to judge the comparative merits of different cultures - in the absence of the very data you're attempting to gather, how else would you distribute attention anyway, other than equally or randomly?
Once you've presented valid evidence one way or the other, of course, the game changes (which is why, in the evolution vs creationism battle where there's a metric fuckton of evidence on one side and fuck-all on the other, the "teach the controversy" thing, with equal attention given to both sides, doesn't fly), but in your boldly assertive post, you haven't given us anything but arrogant dogma.