There are many ways to create "sticky" products, even commodity products (e.g. coca cola, starbucks, etc). Network effects are just one.

Regarding Price to Earnings... I'm not sure everyone fully fleshed out the end game for the frontier companies. It appears the pitch is that this current phase is a stepping stone to Artificial General Intelligence or Super Intelligence. I can understand the perspective of investors though... If you can get half of the world on these products at some point you will find something you can sell them even if its not the core product (i.e. loss leader).