Obviously you can create a new community by driving away an arbitrarily large fraction of an existing community’s membership; this is not a very interesting claim.
Is it not? Why?
In my experience, it’s entirely possible for a community to be improved by getting rid of some fraction of its members. (Of course, it is usually then desirable to add some new members, different from the departed ones—but the effect of the departures themselves may help to draw in new members, of a sort who would not have joined the community as it was. And, in any case, new members may be attracted by all the usual means.)
As for your empirical claims (“it’s very difficult to do so for a community without it being net-negative …”, etc.), I definitely don’t agree, but it’s not clear what sort of evidence I could provide (nor what you could provide to support your view of things)…
Is it not? Why?
In my experience, it’s entirely possible for a community to be improved by getting rid of some fraction of its members. (Of course, it is usually then desirable to add some new members, different from the departed ones—but the effect of the departures themselves may help to draw in new members, of a sort who would not have joined the community as it was. And, in any case, new members may be attracted by all the usual means.)
As for your empirical claims (“it’s very difficult to do so for a community without it being net-negative …”, etc.), I definitely don’t agree, but it’s not clear what sort of evidence I could provide (nor what you could provide to support your view of things)…