Has this been confirmed one way or the other, yet?
For me, it’s a total deal-breaker if it doesn’t.
I appreciate that somebody put effort into making a new soundtrack, but the original is iconic, and one of the best PC games soundtracks made. If I play AoE, I want it to have the original soundtrack, which sounds ancient, mystic, alluring, primordial… especially the opening game track, which is probably the most iconic piece of music in the Age of Empires series other than the title track, and which itself sounds like a revelation in a virgin world at the dawn of time:
The new soundtrack is not as poignant, IMO, its themes not as solidly conceptualized, and is also excessively drowning in reverb, which to an extent spoils the soundtrack that’s underneath all that reverb.
So, just like the original graphics and sound effects are an option (thankfully, as the new graphics are tacky, IMO, and feature a noticeably limited colour variety compared to the original), I believe it would only be properly honouring the original game, its legacy, and its fans to also include the original CD soundtrack as an option.