Alas, your facts are a tiny bit off. The draft ended in 1973, and the Americans pulled out prior to 1975, when the North Vietnamese took Saigon, and the remaining Americans and some of their South Vietnamese supporters left Vietnam in a chaotic disaster. I remember seeing that on television. I was actually 18 for most of the year, as I have a late birthday. If I had been drafted (well, I am a girl so this wouldn't actually have happened) for Vietnam, I would have been 16 years old and a junior in high school, which would have caused my parents no end of upset. (the draft age was 18 but there were some kids my age who forged their paperwork and joined the military as underage folks.)
I could have been a hippie hanging around Haight and Ashbury if only I had run away from home at the age of ten but that would have been a long, lonely, scary cross country trip for a fifth grader. Haight and Ashbury was pretty well abandoned after the Summer of Love in 1967.
If you go by the draft age concept, Generation Jones would go from 1955 to 1965 (we'll grab that first year of GenX because the birth rates didn't really start to decline until about 1966, which was technically the reason that the Baby Boom ended and turned into a Baby Bust).
edit: US combat troops were pulled out of Vietnam in March of 1973, which is the main reason that the draft ended that year.
second edit: the majority of the Haight-Ashbury crowd was probably younger members of the oddly titled "silent generation."