You are conflating belief systems and behavioral patterns. Christianity is a belief system populated by folks who follow Christ as Lord. Full stop.

This Kumbaya Collective you describe is a behavioral pattern that many folks take part in. Some of them may happen to be Christian, others may not.

But to observe that some Christians are part of the Kumbaya Collective and then go on to imply that being part of the collective is a “simple form” of Christianity is a categorical error.

Behaviour does not imply Faith.