I'll try. First I'd say that there are the things that are of the essence of the church. A church that does nothing other than proclaim the gospel is still an outpost of the church. We might label most of these things "theology". There are lots of things that are for the good of the church, but not of the essence. You could have a lot going on, but not be a church if you miss the gospel, but just because they aren't necessary doesn't mean they aren't good. I'd label most of these things sociology. For example, having enough people of the appropriate ages that marriage within the fold is possible is a good thing. There are lots of others. The key thing to realize here is that the LCMS as an institution in places like I serve I believe meets the first, but being honest not the second. All those stories of the generation passing that met at "Walther League", just not possible. It is not the theology that has failed, but the sociology. Call it the church at Philadelphia problem.
Ok, the second part of this is why has the sociology failed? There are lots of answers. One of them is what happened in the late '80s to the '00s, the strip-mining of denominational churches, usually over worship style, toward non-denoms and those that mimic them. These places are essentially sects in that their theology is not shared beyond their walls. They don't play by any rules other than their own. In the article it appears that the CoE is trying to build these now, the same way that many of ours were built by "scaffolding" from the old parish structure. But the CoE has one advantage, they are parishes and not pure congregations. In my experience, we all recognize that we are unable to supply or encourage a good sociology. And that it would be to our benefit to develop some type of institutional response to that. But we can't because in our pure congregational structure there is pull toward being a sect from within. I trumpet my orthodoxy, i.e. I talk a lot about supplying the essence of a church, Lutheran distinctives. And I shy away from any larger "parish" activity that might help with the sociology, because we are all in competition. The CoE doesn't have that competition element. But we do. And it keep us, absent retirements and deaths, from any real institutional response to the failure of the sociology.
Any attempt to re-build a church - not a sect, but a church - that takes its responsibility to serve an area - parishes - is going to have to address that. Philadelphia doesn't close, but it isn't exactly thriving either.