Alcohol is certainly forbidden in Islam.
Whether it is forbidden to the same degree in Qur'an is unclear.
First of all, we should remember that even though the word alcohol has Arabic origins, the substance itself was discovered two centuries after Qur'an.
People at the time Qur'an was initially preached didn't know alcohol. They knew wine from grapes or dates, or beer.
They knew also the distinction between being drunk and being sober.
And of course, they knew that drinking too much wine or beer makes you intoxicated.
According to Islamic tradition, Arabs of the Jahaliya used to drink too much wine and come to salat intoxicated, which prompted God in Qur'an to progressively forbid drinking wine as well as come intoxicated to salat.
However, there is no proof that Arabs in the 7th CE before Qur'an were drunkards.
In fact, I suspect that some Arab traditions already banned wine for religious reasons well before Qur'an.
The reason is that Manichaeism was well spread in Middle East, and it forbade wine, at least for the high priests.
Manichaeism forbade wine not really because wine was an intoxicant but because of its taste, bitter or sour, which reminded how evil is this lowly world.
Coming back to Qur'an, it is "khamr" that is advised to avoid, because there is some good in it but greater evil.
Now, does khamr in Qur'an mean wine and intoxicating drinks ?
Well, if you carefully read the verses warning against khamr, they don't say this is something that is drunk or even consumed.
Khamr is also listed together with other mysterious magic practices, like mayssir or azlam.
They, also, are best avoided in the same way as khamr.
Therefore, if Qur'an warns against khamr, but not totally forbidding it, it is in relation to magic practices, not because it is intoxicating.
So I think we have two options here.
Option 1: khamr is wine, but it's use is discouraged when it's related to ritual practices.
E.g. during the mass in the Catholic church.
Therefore warning against khamr would be an attack against some Christian rituals using wine, where wine represents Jesus' blood.
Option 2 (mine): khamr didn't mean wine here.
In fact, I believe it was not the Arabic word khamr, but the Syriac word khumra.
And khumra in Syriac means amulet, or a kind of amulet.
And now we have a rational explanation why khumra is listed along other magic practices in which there is evil, and therefore should be avoided.
