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What are these magical alternative routes to space the author speaks of? Outside of the atmosphere, the only way to propel yourself is Newton's laws, and that implies a rocket.

In the context of Spacex's more recent successes in innovation, this reads a bit like those "computers will never be smaller than a gymnasium" thinkpieces.

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The most magical is the space elevator.

Mundanely speaking, launching from high-altitude planes or balloons, and using space planes, could save a lot of fuel, as well as allowing for a wider selection of launch sites and, as a consequence, wider launch windows and the ability to change where one launches from at short notice, all of which could help reduce launch costs.

Reaching orbit is the really hard problem he's talking about; once you're up there you have your choice of high SI things like ion thrusters or solar sails - stuff that's useless for reaching orbital velocity but works great in free fall in a vacuum.

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