In re-mastering an older recording, there certainly are new tweaks and tricks that have become available which, especially when you are completely remixing an album, will make an old master sound like it was recorded yesterday.

I know I will never convince you (and just ignore the fact that remastering has been part of my job for years) but I would just direct you to recent re-releases of old black and white films from the 1940s or earlier which by computer techniques have been cleaned up to look like they were photographed yesterday. The advances in the past couple years has been similar in digital audio workstations and their ability to clean up older audio recordings.