Science has not yet actually disproved the Bible. There are some areas where there is dispute between what men interpret of the evidence around them with the default option being that science is correct and Scripture is wrong, which is merely a preference on the evos part with absolutely no solid basis.
While allegory may put things in terms that teach truths, there’s no way that one can say that allegory IS truth. If you take the Bible as allegorical, it’s subject to anyone’s interpretation as that anyone sees fit and that just doesn’t wash.
There are absolute truths in the Bible, that are fact. There are things that can be taken literally, as when declarative statements of fact are made.
By declaring the Bible, or anything for that matter, as allegory, the person making the declaration of the type of literary style of a work, is the one casting doubt on the truth of the Bible or that source. It just comes with the territory.
The truth is; Jesus is real, His death was real. Sin, redemption, heaven, and hell, are all real.
Myself, I always thought Darwin’s writings were a rather crude allegory.