Starsailor and both of the first Plastic Ono Band records were released in 1970, a good year according to my taste in music.
Sad so many will go to their graves with never hearing the beauty in this music.
Around 76, Bowie was inspired by Enos work and stuff that was coming out of Germany. Also compounded with obviously
wanting to go in a new direction, he at the time was going through a divorce, drinking and serious depression, saying the reason also for the instrumentals was the fact he at the time was having trouble writing, finding something to say.
Late 60's and 70's are so far the best and most innovative time for music, some say it had nothing to do with... drugs.