A correction or two:
General Hospital only exists in BW kinescope for roughly its first 8 years (1963-71) though it went to color in 1967. Apparently there a only a few surviving tapes in color prior to 1978, and they're in the UCLA collection.
As to DS, syndication was the main reason for saving the tapes. Back then, each network had its own division for syndicating its old shows. ABC Films was going to put the show out as soon as the show ended its network run, but the FCC intervened. In 1971, the networks were forced to divest their syndication divisions as the result of an antitrust ruling. So, ABC Films became Worldvision, NBC Films became NTA and CBS Films became Viacom. Alll this reorganization delayed the syndication of DS for several years.
Ironically, the networks can now own shows again. Viacom woundup being merging with Paramount, and it now owns CBS!
There ARE some other vintage soaps that were saved. Both Days of our Lives and The Young and The Restless are Columbia/Sony productions and have been syndicated abroad for over 30 years. Since Days premiered in 1965 and was in color from the start, the fact that the archives are complete is quite a feat. In 2005 SoapNet showed the first 2 episodes for the 40th Anniversary. I'm hoping that the network will be smart enough to start showing reruns of the show starting from the November 1965 debut. For all you Don Briscoe fans, he was on the show for a few months in 1966 prior to DS.