I am not aware of any opinions that smoking on Yom Tov is more lenient than the remainder of the year.
But to your point, once upon a time, when the dangers of tobacco were not recognized, there were different opinions on smoking on Yom Tov. The issue is that while melachos in general are forbidden, but preparing food and other personal enjoyment is permitted within specific guidelines. In order to be considered "personal enjoyment", it must be something that most people would derive pleasure from the action, hence the debate in the past if smoking is inherently pleasurable or not. However, today that most people do not smoke and many are repulsed by the odor of tobacco; there remain no grounds to permit smoking on Yom Tov.
It should be added that the majority of Poskim forbid smoking the entire year, and R' Moshe Feinstein zatzal only permitted one to continue smoking if he was already addicted before the dangers were realized, but to begin smoking is certainly forbidden.