That is a really good point.
At the very beginning, when the synthetic one was developed, attempts were made to separate the useful compounds and then make them more precisely target the compounds in certain situations. However, more evidence shows that the synthetic ones may lead to a higher risk of psychosis. That's telling us that cannabis as a plant itself has complicated interactions between all those different compounds. So far, the most important parts are THC and CBD. The synthetic one is pretty much all THC without the counterpart of CBD, which is why there is an increased risk of all the side effects.
Even from our current guidelines or recommendations for the low-risk use, we recommend that people use the natural compound that has THC and CBD together rather than using a synthetic one.