WikiIslam is an Islamophobic propaganda website. Simple as that. Like other forms of history-distorting propaganda on the internet, it is not in any way a viable starting point for serious learning and for that reason I don't want to invest a whole lot of time into engaging with it. Nothing in this article resembles serious historical scholarship in Islamic history, neither in regard to the premises and worldview it is based on, nor the facts upon which it draws. To take an excerpt from the article:

Arabs and Muslims appeared on the world scene in 630 A.D., when the armies of Muhammad began their conquest of the Middle East. We should be very clear that this was a military conquest, not a missionary enterprise, and through the use of force, authorized by a declaration of a Jihad against infidels, Arabs/Muslims were able to forcibly convert and assimilate non-Arabs and non-Mulsims into their fold. Very few indigenous communities of the Middle East survived this -- primarily Assyrians, Jews, Armenians and Coptics (of Egypt).

Having conquered the Middle East, Arabs placed these communities under a Dhimmi (see the book Dhimmi, by Bat Ye'Or) system of governance, where the communities were allowed to rule themselves as religious minorities (Christians, Jews and Zoroastrian). These communities had to pay a tax (called a Jizzya in Arabic) that was, in effect, a penalty for being non-Muslim, and that was typically 80% in times of tolerance and up to 150% in times of oppression. This tax forced many of these communities to convert to Islam, as it was designed to do.

Right off the bat we're deep into Islamophobic narratives. Since time immemorial scholars have been well aware that the Arab/Islamic conquests of the seventh century did not entail any kind of mass forced conversion of the populations which the conquerors encountered, and in many cases they seem to have had no problem incorporating non-Muslims into their armies. Actually, by all accounts there was a strong trend among early Muslims of being opposed to the conversion of non-Muslims to Islam. As the ruling elite of a new empire, they were concerned with protecting their privileges and the conversion of the natives threatened them in this respect, creating an awkward disconnect between the expectations of the actual soldiers who had carried out the conquests, and the universalist promises of the Islamic religion - a major topic of research for scholars of the early Islamic polity. The idea of the Muslims bursting out of Arabia, swords in hand, hunting for converts and full of religious zeal is essentially an Islamophobic fantasy. Recent scholarship, particularly that of Robert Hoyland, emphasizes above all the role of material motivations in pushing forward the conquest, and downplays the significance of Islam. In his view, the Muslim historians (writing centuries later) whose chronicles have long served as our main sources for this period were projecting their vision of a monolithic, overwhelmingly religiously-motivated Muslim soldiery back onto a much more complicated reality. But even before Hoyland, historians have long been well aware that the Islamic conquests were, as far as conquests go, relatively benign. It took roughly three to four hundred years for the majority of the population of the Middle East to convert to Islam, and this for the most part peacefully and gradually. However, in order to serve the Islamophobic narrative, the author needs to be able to say that the Muslims were trying to "forcibly convert and assimilate" the population of the Middle East. Mentioning tolerance would be a no-go. However the author seems to have a basic enough understanding of history that they're aware that they can't leave it at that - the Muslims didn't actually force-convert people, after all. So how does he/she find a way to justify using the phrase "forcibly convert"?

They do so by next bringing up the jizya, that is the tax applied to non-Muslims living under Muslim rule. Here, again, there's no actual history. I don't know what "80% in times of tolerance and up to 150% in times of oppression" is supposed to mean (80% of what? Does the author think the jizya was an income tax?), but it's nonsense either way. The jizya did not come into being fully formed at the very beginning of the Islamic conquests. Taxation in the early period was very uneven and for the most part was simply a continuation of whatever system was in existence before the conquest. It took a couple hundred years for Islamic Law to develop and with it a more standardized system of taxation, but even then there was significant variation according to time and place. The jizya could at times be a heavy tax, but it could also be very light. Most important for our purposes is that in the first century of Muslim rule this tax could also be applied to Muslims. One of the most significant sources of tension within the Umayyad Caliphate was the conflict over whether converts to Islam should even be exempt from the jizya, something which totally undermines the idea that the purpose of this tax was to convert people. Reality was complicated, but the author isn't really interested in that reality, they're just trying to sell you a propagandistic narrative. For that narrative to work, the jizya needs to have been a heavy tax, heavy enough to justify saying that it "forced" communities to convert to Islam. And thus they get to keep the use of the phrase "forcibly convert" in the previous paragraph. The goal is not to educate you, it's to get you thinking that Islamic civilization was evil and oppressive, and consequently, to get you to think the same thing about modern Muslims.

Aramaic/Syriac-speaking Christians did play a significant role as translators of Hellenistic scientific literature into Arabic, though that role, of course, bore no resemblance whatsoever to the description given in the article you've linked. If you're interested in the actual history I'd highly recommend Dimitri Gutas' seminal work Greek Thought, Arabic Culture: The Graeco-Arabic Translation Movement in Baghdad and Early ‘Abbāsid Society (2nd-4th/8th-10th Centuries) (London: Routledge, 1998).