The "stock market companies" is a fantasy promoted by random people, not SpaceX.

What SpaceX shared is that they plan to be "fiber cable" except via space. They'll carry a backbone traffic e.g. between Australia and U.S. via laser links.

Companies that currently pay for undersea fiber cable to carry traffic will pay Starlink for the same service.

Also, a backhaul for 5G operators (see https://www.telecompetitor.com/starlink-update-musk-sees-mob..., https://www.zdnet.com/article/japanese-telco-kddi-to-use-spa...).

Also airlines.