It's not because it's easier to ship, it's because you can double or triple your money...
Example... 1 kilo raw coke...40k [US price] cook that same 1 kilo into crack and now you have 3 kilos of crack that you can easily make 100k or more off in the street
The drug it's self, in crack form, is 10x more addictive then powdered cocaine. The user experience of a "high" only last for a few minutes, side effect being users use the product faster. This is why it's a lucrative market for gangs and street dealers. If you hold territory to distribute your product, you increase your revenue. Cash is what every dealer wants, product is what ever user wants. Supply and demand effects.
Don't know why some may believe people make crack because "it's easier to transport"... no, no its not, especially when you consider liquid cocaine. Yes cartels smuggle liquid cocaine![1]
It's about money.
Cartels have billions & billions of US dollars to spend, they spend big money on R & D too.[2][3]
[1]https://www.usatoday.com/story/travel/news/2019/11/15/housto...
[2]https://www.bbc.com/news/world-latin-america-40480405
[3]https://www.nytimes.com./2012/06/17/magazine/how-a-mexican-d...