Pure fantasy. If 80% of the population had favored Uncle Ho there would have been no mass migration south of people willing to leave everything behind to avoid his rule. There actually would have been a mass uprising in support of the Tet offensive. The North Vietnam Easter-Apr. '72- offensive would have been welcomed with open arms as there were no US ground combat units remaining in-country. Instead the communist invasion was soundly defeated by the ARVNs you are trying to claim actually supported Ho. Fantasy.
On all three fronts of the offensive, initial North Vietnamese successes were hampered by high casualties, inept tactics, and the increasing application of U.S. and South Vietnamese air power. One result of the offensive was the launching of Operation Linebacker II, the first sustained bombing of North Vietnam by the U.S. since November 1968.
Easter Offensive - Wikipedia, the free encyclopedia
Without American air support the offensive would have succeeded. This is why:
"I have never talked or corresponded with a person knowledgeable in Indochinese affairs who did not agree that had elections been held as of the time of the fighting, possibly 80 per cent of the population would have voted for the Communist Ho Chi Minh as their leader."
Source: Dwight D. Eisenhower, Mandate for Change, 1953-56 (Garden City, NY: Doubleday & Compnay, Inc., 1963), p. 372
https://www.mtholyoke.edu/acad/intrel/vietnam/ddeho.htm