But that is still searching track by track, and I have 5000+ compilation tracks that I would need to search on. Obviously not impossible, but depending on how much free time I'm willing to dedicate on a daily basis, it is still likely to take many many months to do.
I have done so much manual searching to fill certain tags, I just can't summon the desire to do it any longer. For example, over 90% of my 2500 albums have album art that is a minimum of 1000×1000 pixels with the highest quality JPEG's I can find. The time I've spent on that alone is many hundreds (thousands?) of hours. In addition, I searched far and wide for album reviews that I populate a custom Album Review field I made… Again, hundreds and hundreds and hundreds of hours. I am burnt out!
If there were a website that showed the track original release year directly with the specific compilation album, that might work. I would only have to search for albums, and all the relevant track years would be captured in one search for a given album. Still a lot of work, but at least doable. That said, I've never found a site that displays it in this way, including Wikipedia.