Backed up iTunes in 2007, now can't play purchased songs because no access to old email, old ID no longer recognized
So..... many moons ago (2007) I used my original iPod and iTunes a lot. At some point, I backed up my iTunes account onto 45 CR-Rs, then got away from iTunes for a long time as an Android/PC user and did more streaming of music. Now transitioned to an iPhone and am trying to recreate my old iTunes with my backups. Seems straight forward enough, but....
The AppleID I used back in the early 2000s was a hotmail address, to which I have not had access since before 2010. The "Find your AppleID" thing says that old address isn't an AppleID, but it clearly was at some point, as I can tell by looking at the purchase info for songs I bought long ago. I find it hard to believe there is no way to reauthorize purchases I made (i.e., music I paid to own, the same as if I had bought a CD in 2000) so that they play on my current account.
Maybe I am an idiot or misread some of the other posts and responses on here (I saw some similar but not my exact issue) and am missing an easy fix/work around. Ideas and help would be greatly appreciated - it sucks that I can't access multiple thousands of songs I bought, still have, but just can't play on any current devices...
Windows, Windows 10