I know it's not intentional, but this question and the one about pork https://www.reddit.com/r/AskHistorians/comments/v1pw9d/was_pork_consumed_by_now_muslim_populations_ie/ fall victim to the idea that the arrival of Islam was this clear demarcation point where everybody immediately stopped eating pork, drinking alcohol, gambling, and doing illicit sex stuff.

The reality is that the arrival of Arab/Islamic armies probably meant very little to great majority of the population living under their rule. The Arabs were for a not insignificant time, at least a hundred years, a minority ruling party and were happy to allow their Christians, Jewish, Zoroastrian, Hindu, etc. subjects keep on keeping on if they paid the jizya (the tax on non-Muslims in exchange for their protection) and did not cause a ruckus. There is some debate on if they wanted converts or not, but some Arabs did find it incomprehensible or unseemly for non-Arabs to be part of their religion.

What that means is that the diminution of drinking culture happened gradually and not completely and probably had continuities with what came before. That's why using sources like the Hadith, the Quran and other sources that come after the pre-Islamic period can provide us a sense of what was drank before.

The most specific drink mentioned in the Quran is Khamr or wine. It was the alcoholic drink of choice for the pre-Islamic Arabs, and one that is prohibited in the Quran with 5:90-91

"O believers! Intoxicants(Khamr), gambling, idols, and drawing lots for decisions are all evil of Satan’s handiwork. So shun them so you may be successful. Satan’s plan is to stir up hostility and hatred between you with intoxicants(Khamr) and gambling and to prevent you from remembering Allah and praying. Will you not then abstain?"

This what the Encyclopedia of Islam says about how the wine got to the deserts of the Arabian peninsula (Joseph Sadan, Khamr):

"it seems to have been imported from Syria and lrak; in early Arabic poetry the wine-trade is chiefly connected with Jews and Christians, who pitched their tent (hanut, also a loanword from Aramaic) among the Bedouins and provided it with a sign denoting its character. In it entertainment sessions were held, in the company of female singers who often also belonged to the establishment. The wine was kept in jars or skins, provided with a mouth-piece which was closed by means of a string."

Ironically, the spread of Islam probably introduced a great familiarity with viticulture as the Arabs entered areas like the Fertile Crescent and Iran where wine's history reaches as far back as civilization itself.

While it can be debated whether the drunkenness of the pre-Islamic Arabs was exaggerated to show the piety of Muhammad, what we have states that they liked to drink a lot. We have their wine poetry, which eventually developed into its own full-fledged genre in the Islamic world, and Hadiths like this also from Sadan's entry on Khamr

"Tradition has not refrained from describing how Hamza b. Abd al-Muttalib, Muhammad's uncle, in a fit of drunkenness mutilated Ali's camels (Bukhari, Sharb, bab 13; Khums, bab i; Muslim, Ashriba, trads. i, 2; Maghazl, bab 12; Abu Dawud, Kharad/i, bab 19). The commentaries on the Kur'an also relate how Muhammad's companions held drinking-parties which caused them to commit faults in ritual prayer (see al-Tabari, Tafsir, ad sura XIV, 44; Muslim, Fad'il al-Sahdba, trad. 44, cf. 45; Ahmad b. Hanbal, i, 185-6)."

Now what adds another layer is that there was a lively debate among Islamic jurists and scholars on what exactly Khamr meant.

Did it mean grape wine, date wine (which was more common in Arabia), any type of drink made of grapes, or any type of alcohol at all? You can see the problems with translation because that ambiguity is completed removed in the English by using the word intoxicants, not wine. But that lively debate is for another time. What's important to note is that because of this debate most Islamic scholars who write on drinks provide a typology of drinks and weigh in on if they should be forbidden or not. From that we find out about other drinks like.

Beer(Mizr or Fuqqa) which has equally ancient roots in Egypt and the Fertile Crescent, Iran and continued on after the arrival of Islam.

Buza- A fermented cereal beverage related to beer, that is like a slightly alcoholic gruel. Make sure to drink with a straw.

Other fruit infusions- There was a worry among the pious that steeping fruits, apricots, date, etc. in certain containers for a long time may result in fermentation, which implies people were aware of how to make the alcoholic varieties.

Kummis- Fermented mare's milk that was an ancient beverage of the Turkic step peoples and came to the Islamic world with the Turks in the 9th century.

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Sources

P. Bearman et al. (eds.), Encyclopaedia of Islam, 2nd ed., Brill, entries

Joseph Sadan, Khamr

Joseph Sadan, Mashrubat

J.A. Boyle, Kumis

Rudi Matthee, “Alcohol in the Islamic Middle East: Ambivalence and Ambiguity.” In Phil Withington and Angela McShane, eds., Intoxication and Modernity (Oxford: Past&Present, supplement, Nr. 9), pp. 100-25.

Also, if you're interested look out for this upcoming title by Rudi Matthee

Angels Tapping at the Wine-Shop’s Door: A History of Alcohol in the Islamic World, Hurst, 2022