But from an optical and electronics point of view, it's much harder to process the return signal that way, and probably uses a lot more energy due to the processing required (with current tech).
The reason is that you can time-gate the noise out that would otherwise be hitting your correlation accumulators if you have a vague idea of the supposed delay/ToF for the pulse.
However, once you add mechanical scanning, at least for systems with not that many orders of magnitude between range resolution and maximum detection range, you can use systems like mode-locked lasers that for example have around 0.1% native duty cycle, circumvent the issue of peak power through the aperture/scanning 's spatial focusing (each pixel only needs a managable amount of energy, and delivering that in a single pulse won't require unreasonable peak power levels), and still get all the energy-efficiency benefits of single-pulse ranging vs. spread-spectrum/correlation ranging.
The only but major downside is the requirement of mechanical scanning.
That's where the beam diameter at the target is much larger than the target, as for aircraft. With a small scanning dot from a LIDAR and a nice big target like a car, almost all the power hits the target, but you still have inverse square losses coming back.
Second part of the comment I omitted is was what You mentioned in the beginning. Those 20-30 meters of practical range is why we keep seeing small LIDAR sensors on things like iPhones / iPads (though there I believe the range is even a bit shorter due to the size / power constraints), but not really much beyond that.
For practical demo of what's currently available at the high end of solid state LIDAR (albeit at 40k+ USD), I'd suggest looking at Leica and their BLK2GO PULSE (solid state) vs the rest of the BLK line (rotating laser spot).