Not sure I'm following your points here. You suggest that the church needs to keep and maintain a community, but doing things that attracts such potential members is inappropriate? I'm not really understanding what the idea to get new members is. Outreach and knowing your audience are important factors in growing a community.
One way to attract members is to showcase that the things that matter or are interesting (within reason) to potential members matters to the current members. People tend to be attracted to people that at least appear to understand them. Highlighting that everyone around you is wrong and doesn't get it kind of pinpoints a major underlying issue with the church today.
Unfortunately, the reality is that every group needs a way to attract members and increase attendance. I'm providing one from 1400s Germany, and some areas in Germany are, to this day, prolifically religious (bavaria, for example). Maybe it turns out it was a good idea to do what you can to keep members?
That's the part I'm not understanding. So how do you recruit new members if you exclusively advertise to people that already agree with you? Your audience is explicitly people who already are part of your group, and that number continues to decline.
There are two groups to try to entice - current members who are losing interest, and non members who are currently non believers. If you only create events that are catering to current and active members, you alienate the others and won't grow