It is an interesting pitch. So far the two "biggest" companies involved, Boeing and Blue Origin, have yet to demonstrate their ability to execute on more modest goals, much less this giant vision, so it is difficult to take seriously.
BO needs to figure out why the BE-4 engine has been such a challenge, and Boeing needs to figure out why Starliner has been such a challenge. If they credibly re-build the teams on those projects and turn them around, then perhaps that will inform their efforts on something grander.
I'd say part of the BE-4 failure to deliver is around culture, they're using the old playbook and not an agile process. Plus they've had a lot of staff leave, although that's been fairly recently after the shennanigans the management were playing. The consultancy that B.O. secretly asked to do around SpaceX was pretty eye opening.
Although, granted, even with waterfall style it should have been delivered already.
I have read and heard a variety of reasons why BO is not able to execute, some from the press, some from people I know who either worked there or were close to someone who did.
Culture is a defining characteristic of an organizations ability to execute against a plan or vision. So I agree it is a large part of the problem, or more simply a great place to start on the solution.
BO needs to figure out why the BE-4 engine has been such a challenge, and Boeing needs to figure out why Starliner has been such a challenge. If they credibly re-build the teams on those projects and turn them around, then perhaps that will inform their efforts on something grander.