Rabbi Natim Tzvi Finkel says that during the High Holy Days the inner dimension is joy and the outer is trembling, while on the festivals the opposite is true
One source
What the source said
Kan EnglishSukkot, and what it means to be happy on the holiday
“During the Yamim Noreim, the inner dimension is joy, while the outer dimension is trembling. And on the festivals, it's the other way around.”
Listen from 9:29Reported by one source so far. It is confirmed when a second, independent source reports the same thing.