Well, yeah, but building something tall enough to reach the synchronous orbit is impossible even on Earth, there’s no material with even a thousandth of the com

Well, yeah, but building something tall enough to reach the synchronous orbit is impossible even on Earth, there’s no material with even a thousandth of the compressive strength required. Space elevators are only possible because they’re tensile structures and the “bottom” that supports the weight of the entire structure is up there in a low gee environment. Remember that just getting outside the atmosphere is the almost trivial part of rocketry compared to the problem of having to then accelerate to >= orbital speed fast enough to not fall down! And anyway you’d have to dismantle the planet to build your launch tower, which I guess would solve your problem, in a fashion. Though – whatever you turned your planet into would just have an annoying tendency to rapidly collapse back into a ball.