As for why the Kinect interferes with other units, it's because of the imaging modality (structured light). The sensors interfere with one another because they're largely dependent on detecting a specific pattern of projected dots. If you detect too many dots or if the image gets saturated, you start to have a problem.
In the case of traditional scanning LiDAR (e.g. terrestrial LiDAR in the sense of a Leica or Faro or Velodyne unit), this isn't necessarily the same case. Sure, if the two lasers point exactly at each other for a given point over their sweep, then at that point the lasers will saturate the measurement and that specific measurement will not be useful. In time-of-flight based, mirrorless systems, this matters less than one might think. I can see this being consistently a problem when scanning with Velodyne tech since they tend to only rotate about one axis, but for other types of LiDAR I don't think it would be as big of a deal. Granted, then you have to worry about scanning speed and how that affects the final results.
Overall, I don't think that unit interference is going to be a significant factor in adoption. LiDAR is a broad technology and it's not easy to make assumptions about the entire industry based on a couple implementations or modalities.