Valid points, Vajra Protect.
In any case, outer growth does not reflect inner growth.
Whether a center has 10 members or 1000 members, what truly matters is how the students are transforming or not.
A true Guru would be most concerned with one's inner growth and not outer growth. This is the whole point of transformation.
I know my Guru could not care less if our center is getting more members or not, or if we remain small. But he is most concerned about how we, his students, are transforming or not.
Perhaps, in the future, there would be reincarnated Tulkus who would deliberately choose not to be recognised and live among the masses to remain incognito and influence from the grass roots without being known. It is very possible.
Bodhisattvas will always find the best and most beneficial ways to help all sentient beings. They will choose to appear where they need to appear and as whatever form that is best.