Worth noting that Hexbear(currently makes up 25% of all posts on lemmy) only saw a deflation in the initial weeks after launch. It then stabilised and didn’t deflate at all over the course of 3 entire years of operating, it happily ticked along with new users coming in at the same rate as user churn. If other communities establish themselves and actually foster a real community that wants to maintain the space there will be an initial deflation but then people will just stick around visiting daily.
A culture of simply permanently moving here should be something people work to establish.