There is a multitude of reasons why people have disengaged: rational and irrational fears and people taking legitimate caution are probably the two that would be the most talked-about and accepted.
I believe however the real reason why people have disengaged lies in a lack of true pre-pandemic relational connections.
If people are connected to other people in a meaningful way, they will not as easily drift away. If people were actively engaged in a discipleship relationship, there is an even greater chance that they would have remained connected. Honestly, I think many people had very superficial relationships with their churches they identified with pre-pandemic. Churches have swung towards providing a really good experience or “show” on Sundays and people naturally became consumers. Providing a good experience for people to consume is always easier than digging into relationships because people are messy. A lack of relationships and real engagement beyond "the show" has resulted in a lack of "glue" that helps people stick around.
I believe the key is for churches to change their ministry models. For too long churches have leaned into and created a "come and see" style of ministry. If on average 64% of people have yet to return churches should shift 64% of their efforts toward those who have yet to return. Take ministry outside the walls of the church. I am not talking about online efforts. I am talking about engaging with real live people! Do attendance in reverse. It should be easy to determine who has not returned if you kept good records pre-pandemic. God has called Pastors and churches to "shepherd their flock." Their flock is their flock no matter where they are! Jesus even encouraged leaving the 99 for the 1. In the same way, churches must find creative and new ways to engage those who have yet to return. If not, the natural drift away will only continue. I believe that some of these creative and new ways of doing ministry outside of the walls of the church are really "not new". I believe these are more of a "Back to the Future" model using some "throwback" ministry models. I have written about some of these things in a blog titled "Ministry Reimagined." I have even included nine downloadable volunteer job descriptions that can be filled by churches to help them reach those how have yet to return.
We are in such a pivotal time. The church is not helpless and does not have to accept these numbers. The church has a say in this if they are willing to fight for their flock! It all starts by viewing your people as the shepherd views his flock. Now go after them!