Part of the problem with this argument is that for them to be worth a lot, you need both the amount of stuff launched into space to go up massively and for no one else to be able to build a rocket that's anywhere near as good. Spacex is doing really well now, but if Rocket labs, China, Blue Origin, or anyone else manages to make a rocket that's half as good, spacex needs to maintain a monopoly despite not having anything especially magic.