I don't usually answer you dumb smart nikkas but I'm bored right now
For one, slavery in North Africa predates Islam by millennia. Islam did not introduce slavery to the world, it merely regulated what was already a pre-existing institution (more on that later). To suggest that these Libyan bandits, who aside from enslaving mostly
Muslim Africans also kidnap people, torture them and extort money from their relatives, are being driven by religious injunctions instead of basic opportunism is not only intellectually dishonest, it's also downright retarded
As for the quote that you posted, its an extremely biased, decontextualized "analysis" of those verses
They were revealed at a time when you could literally kidnap a random person in the desert and sell that person into slavery. You could even be enslaved if you owed a debt that you couldn't repay. You could also be born into slavery. Within that context, the verses actually
restrict the conditions under which one could become enslaved to such a degree that
only captives of war (regardless of race) could become slaves. 1400+ years ago, that was actually quite an improvement
Compare that to how slavery was practised elsewhere in the world
Slaves also had rights. They received a salary, could eventually buy their freedom, their offspring were born free, you could not beat them etc. They were more like servants than "slaves" in the Western understanding of that word.
Some "slaves" even became kings (the Mamluk dynasty in Egypt was established by European slaves. "Mamluk" literally means "someone who is owned" i.e property). Some of the most renowned scholars were slaves. It was a completely different system to what we know in the West.
Also, the first verse is addressed to Muslims in general and is not restricted to the Prophet (pbuh).
Aside from that, there are plenty of verses that strongly encourage the freeing of slaves and there are many sins for which the atonement is freeing of slaves. The legal consensus amongst the scholars (both classical and current) is that the trajectory that was set by the Quran and Sunnah was to eventually abolish the institution altogether. Contemporary scholars use this argument to argue for why
re-
instituting slavery is illegal in our current times. It's the argument that they use against ISIS for example.
The Quran does not command us to enslave, it merely regulates the slavery that was pre-existing in Arabia at the time of revelation. That's also a very important distinction to keep in mind.
Then there's the whole issue of how Muslims actually approach the Qur'an which many non-Muslims do not seem to understand.
This is generally a much deeper intellectual debate than you're making it seem and there are a lot of different issues to consider. You haven't even grasped the basics.
1) the Quran is NOT a legal book! It's not a collection of rulings. It's primarily a book of spiritual guidance although it does have SOME clear injunctions, but it cannot be used as a law book per se. There are entire sciences that are developed for the purpose of deriving legal rulings. I can't, as a Muslim, just pick up the Qur'an, read a verse and then derive a ruling from that verse on my own.
2) the Quran is not the only source of law and it's not even the only source of revelation (The authentic Sunnah is also part of revelation). In order to derive legal rulings, Muslim jurists have to know the context of the revealed texts (Asbaab al-Nuzool), the principles of legislation (usool al-Fiqh), they also have to know and understand the specific context of the person/people to whom those legal rulings are to apply.
Even the local culture and customs have to be considered ('Urf). Some things that are deemed permissible in Indonesia, could be impermissible in, say, Morocco or Saudi Arabia. The point that I'm trying to make is that in order to derive rulings in Islam, you have to either be a trained jurist or you have to defer to a trained jurist.
3) as I've illustrated, the law making process is extremely complex and not as simple as looking up a verse in the Qur'an and voila! you have your legal ruling
That's the first issue that you need to understand.
Secondly, wrt slavery in specific, you need to differentiate between slavery as it was practised during the time of the Prophet pbuh and the East African slave trade. Those were completely different eras and the institutions were also completely different (separated by centuries). Compared to how slavery was being practised around the globe at the time of the Prophet pbuh, the former actually
improved the conditions of slaves, encouraged the freeing of slaves and placed strong restrictions on who could even be considered a slave.
The latter (East African slave trade) actually breaks several Islamic laws. Raiding innocent people for the purpose of acquiring slaves is illegal, mutilating human bodies (castration, branding etc) is strictly prohibited, etc.