HTFSE is cheap comparative to fully refined cannabis terpenes and anyone running butane can make it if they have access to decent material. If by “hard to get” you mean “can’t order it with a credit card” then I guess so. If we’re talking strictly the best way to do something, then HTFSE or even some properly decarbed live resin will always be better.
Going the cheap route and just doing distillate plus terps is never going to yield the real effects of a strain, regardless of where the terpenes came from. So to say that just opting for hemp or cannabis derived terpenes makes a distillate cart have unique effects is highly exaggerated. I think adding cannabis terpenes to distillate is like putting a spoiler on a Toyota Camry. The cannabis terpenes play a role but without the other parts it’s still just going to be a distillate cart that just tastes slightly more like cannabis.
There are hemp derived live resins/BHO on here that do an excellent job at filling in the gaps, so to speak. They contain a lot of the pieces of the puzzle that are lost during distillation of cannabinoids but are too heavy to exist in steam distilled terpenes. Distillate + BHO + 3-5% cannabis terpenes is going to cover all the bases.