Isolating salicylic acid from willow bark and then a century later synthesizing acetylsalicylic from salicylic acid were all major achievements in medicine. It wasn't some sort of evil scheme.
I'm also guessing synthesizing acetylsalicylic in a lab is better than growing willow trees in almost every way. Less resource intensive, more environmentally friendly, cheaper, easier to scale, and faster production.
The "natural is always better" (for varying definitions or "natural", of course!) argument is silly.
"heavy refinement, solvents, chemical processes" are all just scare words. They don't mean anything useful. I can use those words to accurately describe cooking my dinner.
The process of taking willow bark and turning it into a consumable product is not minimal, whereas taking cannabis and turning it into a consumable product is very minimal.
From a practicality standpoint, it is simply logical that medicine derived from cannabis is superior to willow bark.
How did you get this idea? Scrape some bark off a tree and steep it in hot water. You now have a consumable product.
I can't find the link now, but I recently read a paper from Israel about how the effects of CBD acted in a bell curve when administered alone, but were much more linear when taken as part of a whole plant.
There are many cannabinoids, and they do often seem to work best when taken together.