The bible is a collection of books divided into two testaments created over several hundred years in three languages by about 40 authors, some of whom claimed to be inspired by God. The Qur'an is one book authored in 22 years in Arabic out of the mouth of one man claiming that every word is verbatim from God. The former is like a menu, while the latter is a fully-plated meal - no substitutions. This allows for the bible to be read 'a la carte'- I'll order the NT with a side of OT. Hold the Deuteronomy. Many Christians that I know do that very thing.
Note: The first 86 surahs of the Qur'an are from Mecca [610-622], while the last 28 are from Medina [622-632]. I consider those groupings to be de facto testaments, especially due to differences in tone and content, but they are compiled together without regard for chronology so that they appear to be one book.
So far, so good?
The Bible is easier to situate in a historical context, even if we understand it’s not a historically reliable document.
The Bible is more self-contained whereas the Quran assumes a significant degree of background knowledge of Abrahamic traditions, and is frequently in dialogue with these traditions even though they are not explained in the Quran.
It also contains far less narrative, making much of it opaque, vague or hard to understand.
From the mystical letters to passages about the 2 ilafs to the identity of the Sabians and numerous other things the original understanding seems to have been lost in between the time of Muhammad and the beginnings of the formalisation of Islamic orthodoxy a century or so later.
As such we don’t really understand all that much about the environment in which the Quran was formulated, who its audience was, its role in its environment and numerous other things we take for granted about many texts yet are uncertain regarding the Quran.
Most of our information for the Islamic tradition is from centuries after the fact, and sometimes seems to contradict earlier non-Muslim information.
As such, how we understand much of the Quran is anchored in sirah-maghazi and hadith traditions that were not written down until a couple of hundred years later and are of questionable veracity. So the equivalent of the Bible is really the Quran
and related traditions.
Much of these, especially the “occasions of revelation” stories whereby we are told verse X was revealed to Muhammad in response to some purportedly historical event, are pretty clearly fabricated to explain ambiguous passages of the Quran and have no plausible historicity. When early exegetes don’t understand a verse, but centuries later there are clear, detailed stories that explain it perfectly, one might question why this is.
It is increasingly uncommon for people to view the Bible as historically accurate, especially among those opposed to Christianity, yet popular understanding still seems to accept the Islamic tradition as being broadly accurate, both among pro and anti-Islamic factions.