If you're going to actually cite a study, you should maybe link the actual abstract itself instead of some random article that regurgitates as little info as possible.
If you actually read the study itself it says that they "dabbed" the extract at over 700 degrees F, which is not how most people dab. When you put a dab into a banger at that temperature there is definitely some combustion occurring, which would result in benzene. But if you're dabbing at temperatures that a normal human would actually do, you're looking at temps between 450-600. The basis of the study is flawed in that it is not even emulating how people actually use these products. The lowest temperature that they tested (322°C) is slightly above the highest temperature that most people usually dab at. While these data points are very important to have and be aware of, citing this study the way you are is disingenuous to the conversation that is being had. Most things when used improperly can be dangerous, as this study shows.
No one said anything about a stronger high. And what you said proves that amphetamines are a dangerous drug, prescription or not