They do have “better” genetics now. Almost no one is growing the old long flowering varieties on a large scale anymore. I’ve seen recent documentaries and the buds they were pressing into kilos don’t even look bad. Looked like regular halfassed outdoor. Chunky nugs that were actually trimmed OK, not big leafy spears.
Cartels aren’t dumb. They are very aware of the US market. They know they have to compete a little. The economics of it demands it. It’s also more economical to get bigger yields of faster flowering plants. 2 crops done in the time it previously took to make one.
Saw the same thing on a documentary about a Jamaican ganja farmer. He was growing skunk and blueberry in a little plot he eked out. Short, quick wide leaf plants.