Achdus proves nothing as quite often you find the most achdus when people are doing an aveira as the yetzer hara makes achdus so more people should sin together. Additionally you find a concept that enemies make peace when they have a common enemy to defeat so achdus in no way proves anything. Theres goo dachdus and bad achdus and I am not saying this is bad but just explaining that achdus means nothing in and of itself.
Spiritual feelings prove nothing as well. Im sure Christians Buddists… say they have spiritual feelings when they do their “mitzvos” so again dont judge by the feelings.
Selichos is not about being lively it is not a “feel good” event.
You are supposed to feel low and recognize that you are steeped in aveiros.
The feel good is reserved for Succos and yommim tovim in general. Selichos is not an upbeat event. The fact that so many people went just shows us how many people are so out of touch of what Selichos is all about.
All those people need to “Asei lecha Rav” they need to find a true Rav who can guide them (not Yehuda Green as he is not a Rav at all as opposed to Carlebach who at least was a big talmid chacham).
Truly a wasted opportunity for all who went but more than that it fed them wrong Hashkafos and fooled them into thinking they did something good and were mekayim Selichos the way it was supposed to be.