What, seriously? Damn, i had no idea. They teached me some "sharia does not allow slavery" thing on high school, so i'm guessing my teacher got his things wrong.
Yes, seriously. There was an east African slave trade which lasted far longer than the west African/Atlantic trade and moved far more people. That trade was entirely in the hands of Muslims and the colonial powers which suppressed it were obstructed by Muslims.
As for sharia not allowing the enslavement of Muslims, I'll point you to the current day nation of Mauritania.
All religions are human constructs and as such are as replete with as much hypocrisy as all other human constructs. When you make something up, you also make up loopholes, exceptions, and "work-arounds".
Well, guess the 'jungle routes' thing is also a myth.
More hyperbole than myth. Certain populations were able to escape general enslavement/serfdom thanks to the extreme terrains they lived in.
Yeah, but wouldn't it be a longer route?
Longer in distance, not in time. Remember, we're dealing with sailing ships which depend on wind. Wind conditions are going to make some places harder to reach by sail.
Well, does it need to be sugar?
Sugar is what drove the demand for slaves in the OTL because it was already known in Europe and the demand for it was essentially infinite.
They could set up plantations of something else that'd be profitable, preferrably a new world product...
The trouble with a New World product is that it first needs to be identified and then a market for it developed. Tobacco, for example, wasn't a slam dunk. Raleigh and the others didn't bring back samples which immediately sparked widespread demand. It will take decades or longer for a previously unknown New World product to become accepted in Europe.
Even though they could just plant it on their own lands, like the potato plantations on Ireland. So i guess you're right again.
Potatoes weren't a slam dunk either. IIRC, as late as the mid-1700s Frederick the Great had to eat a dish of them in public to convince his people they weren't poisonous.