The songs I have learned first hand are like companions who are always with me. But I like to sings two versions of a song in tandem, one of which is my companion and the other of which is something I learned from a CD or the internet etc. I am 76 and I find sometimes that I have to stop to remember the opening line of the other song. It's like priming a pump: once I get the 1st line the rest flows naturally.
Those of you with a tradition of singarounds don't realize how lucky you are. Here (roughly Floyd VA) there are mostly two types of singers, performers and contestants. I have listened to Mary Lomax sing songs from her Ballad Book, sometimes stopping to look at a verse or two. And no, at 88, her voice is not so good as Joan Baez's. But it was a great privilege to have heard her.
If you require polished performances, you will eventually get the top acts; what you will lose are the songs that have hung on for centuries and then disappeared.