I think motivation plays a large part in whether something is holy or heathen. If a wear a dress with the intention of being modest, and pleasing God, I think that can be called "holy". (In the following context.)
I Peter 1:15 But as he which hath called you is holy, so be ye holy in all manner of conversation;
holy- sacred, blameless, ceremonially consecrated
conversation- behavior, consecration
BUT...Last time I checked, even prostitutes wear dresses, so wearing a dress in and of itself would not make a person "holy." (Or heathen...due to some assocation with a prostitute who wears dresses.)
Unfortunately for all those who would like to judge by outward appearances, motivations, unless they are professed for all to know, can only be known by God, so it is impossible to judge by a mere photo whether someone is "holy" or "heathen" based on one piece of information (unless the photo is extreme in one direction or another).
It may be possible to tell that someone is heathen if the outward appearance is obviously so, but since there are so many different cultures and an equal number of reasons for growing one's hair long, then long hair is not obviously Apostolic or "holy", so the conclusion isn't possible.
The only conclusion we can draw from a photo of someone who practices something similar to some Apostolics is that they might
possibly practice something similar to Apostolics for similar reasons.
I actually think its easier to conclude someone is heathen than if they are holy...because even those who may appear holy, may still have unholy hearts.
Personally, I think its just a Guinness BOWR tryout, but that's just my hunch.