Jets breathe atmospheric air for combustion because they operate in an atmosphere where oxygen is readily available for combustion. They have an air intake nozzle.
Rockets carry their own oxidizer because they must. They only have an exhaust nozzle.
Consolidation is inevitable in industries where huge capital investments are necessary to build a viable product. The only way a new manufacturer will appear is if a major government decides to finance it for strategic reasons regardless of economics.
I can think of three occasions where this happened: Eurofighter with the RR based Eurojet engine, Rafale with an engine from Snecma and the A400M with a specifically designed turboprop. None of these manufacturers rose to challenge GE, RR or Pratt and Whitney when it comes to mass produced turbojet or fans.
As much of a fan of SpaceX's vision as I am, the only ballistic point to point passengers I can envisage any time soon would be military operatives in a dire emergency.
I just can't see the likelihood of ballistic weapo..er.. projecti..er.. vehicles being allowed anywhere near major population centres, by tens of decamiles, therefore mooting the purpose of such extreme point to point passenger journeys.
Never mind the sonic booms and general noise. Even having regular scheduled passenger landings on water seems ... not entirely environmentally friendly.