Although you may feel as though the "bus" has past you by in that you're only finding out about them now, the vast amount of recordings made over the years will give you a lifetime of enjoyment.
You're also lucky in that you are learning to play their music because it gives you an inside look at what they were about. Instead of just listening to them and thinking oh, I like this jam, you will find that by playing their music, if only simply, it will afford a glimpse into their genius, and of course the extremely rare gift that Garcia had. Someone like him, with the circumstances of his day, only happens probably once in all of history.
You're only a few years removed from it all.