No, LEO isn't safe. We aren't safe anywhere. I do think we can maintain LEO as useful, and safe enough for satellites. Starlink satellites lower orbits must be kept in orbit by using thrusters; otherwise, air friction slows them down and they fall back to Earth. Thus, the worst mass of orbital debri, enough to prevent a rocket from launching higher than 300 miles, can be cleared, theoretically, by launching a trash collector in a very low orbit, and collecting trash from higher and higher orbits. All the trash can be deorbited into the ocean.