excellent! thanks. I had no idea the hash was so lame too - you'd think the Lebanese et al would've known better.
lol man the traditional hashmaking cultures did know better and very melty high quality hashes have been made by these guys for a long time - however the best hash that gets made typically is the hashmaker's headstash. The shit that gets exported is exactly that. You think that the shit that gets sent overseas is gonna be the best? Think again! 'Export quality' has always meant lesser hash from these regions - also there are obviously problems of storage in transport and smuggling is not an ideal circumstance to keep hash at it's best!
The studies cited on that website (thanks for sharing that one
@Baron23!) are about illicit seizures and appear to be all US based studies. There are hardly enough samples used throughout these study of hashish to be considered statistically robust/representative of all the material available and the page does highlight this. Moreover, we can see that the THC levels rose in hashes sampled more recently after the late 90's, this is where the advent of bubble hash would have likely had an influence and Americans would have started making more local hash. In more recent times again, obviously with the advent of dabbing we now see more striving for very melty, higher quality hash to suit this new method of application.
This raises another factor - remember that in the past (especially before dabbing), many would have just smoked hash in a joint or in a bowl with a flame. Super ultra melty hash can actually be counterproductive in this scenario, where the melt could drip off your doob or melt through your rig.
In earlier times, we can see that hash is much weaker, but considering that this is no doubt the abovementioned low quality export hash from traditional hash-producing countries being consumed predominately using a flame rather than vaporization, we should not be surprised to see it being weaker than the newer methods that came about more recently made from more potent American flowers with newer techniques that were intended to be consumed differently.
However if you check out some old school documentaries of Pakistani and Afghan hashmakers they make melty high quality hash. The first hash that is beaten through the screen is always the meltiest. This material likely stays with the hashmaker in most cases as there is much less of this than the later, lesser grades of hash.
By the way, you equivocate THC% with potency, which is problematic. In my extensive experience with higher terpene containing concentrates (full melt bubble hash), 50-60% THC with 15-20% total terpenes is markedly more potent than a concentrate with 85% THC and 5-8% terpenes from the same flowers (your typical 'high THC' concentrates). Also having dabbed pure THC, it is a relatively 'directionless' high that is not especially enjoyable alone without other terps. It's all about the overall terp profile (including cannabinoids, which after all are a kind of terpenoid!).