The "network effect" argument for Bitcoin... is almost always made in a vacuum, disingenuously.
Bitcoin is a microscopic part of, in order:
(1) the internet
(2) PC/cellphone industry
(3) commodities
(4) commodity/securities exchanges
(5) banking and financial services
GLOBALLY, none of these economic sectors has a strong "network effect"... except for unusual outliers.
I suggest the opposite of what you say is true.
Wikipedia . . .
In economics and business, a network effect (also called network externality or demand-side economies of scale) is the effect that one user of a good or service has on the value of that product to other people. When network effect is present, the value of a product or service is dependent on the number of others using it
(1) The Internet began as ARPANET which was a method to interconnect numerous incompatible networks - none of which survive today because users were drawn to the largest compatible network.
(2) mobile phones, I suggest that Android is move valuable than Windows phone for developers because more people use Android.
(3) commodities, I suggest that sugar is more valuable than stevia for bakers because more people use the former.
(4) commodity/securities exchanges, I suggest that the NYSE was more valuable than the Philadelphia Stock Exchange for traders when the latter was still independent becuase the NYSE had more traders using it.
(5) I suggest that JP Morgan Chase Bank is more valuable than the local bank down my street for customers, because more people and businesses bank at Chase.