SpaceX competition: Arianne space and a bunch of upstarts, plus every other commercial launch service excluding the Russians at the moment.

Tesla's competition: every other car marker.

The other space companies don't have the cost structure advantages of reusability.

An advantage that we cannot be sure exists to begin with since SpaceX isn't piblishing financials. And for some launches Arianne Space is already now competitive using the Arianne 5, by all means an out dated design, one that was initially intended to carry a European space shuttle into space.

More generally so, I have no idea why people expect any company to own a market completely. Any market is usually big enough for one than one company to be successful.

Spacex has literally no competition. No one else has reusable rockets and starship will soon be a rapid reusable heavy launch vehicle.

SpaceX's product isn't reusable launches it's just launches, the reusability is their competitive advantage. There's a lot of other launch providers out there.

Just pray that the cost isn't 10 times normal one and can only be used 9 times.