I believe it has healing properties, the bulk of which we don't fully understand yet. That's I believe is in part due to the failed "War on Drugs" by Nixon, Reagan etc.
A drug that's highly illegal isn't as likely to be widely studied as something that's legal IMO.
I've read many reports through the news / online etc of people with medical experiences with cannabis (in different forms) extolling its virtues as a "miracle" when no other modern medicine has even come close to easing their symptoms.
I'm not saying it's safe, and I'm not saying it's right for everyone.
However, I firmly believe that it *does* have benefits and should not be lumped in the same sentences as other illegal drugs like heroin etc, which it often sadly is. You say the words 'Cannabis' or 'Marijuana' to a white middle class conservative and you'll probably get the same reception as if you'd said "Can I give your toddler some of this crack and heroin?".
If course this is all based on the assumption that you're talking about refined cannabis oil for ingestion.......and not hemp hand cream
In a very simplified version of what I've learned by being a nerd who spends lots of time sat on the toilet browsing the internet, there are two main components to cannabis, CBD and THC.
THC is the bit of it that gets you high and sleepy.
CBD is the bit that has the most medicinal properties.
Years ago, marijuana was more of a "Here's the plant, you get what you get" but as technology has grown, and the use of it has become so widespread (Uruguay completely legalised it in 2013 IIRC, and it's now legal medicinally in the majority of the US states).....it's pretty much become a science with different strains exhibiting different structures and complexities.
So now you have strains of marijuana that have been bred specifically to have very little THC content and high CBD content....so the medicinal effects can be obtained without actually getting 'high'. It's these high CBD versions that are often refined into oils and are the ones that I've been reading about.
Even including being given to young kids (oral syringe to deposit oil into the mouth IIRC from one documentary) to reduce a nightmarish life of dozens upon dozens of fits a day. (I'll see if it's still in my YouTube history).