Why isn't there an airprobe for other protocols ? (3G, CDMA, LTE)

I have successfully used airprobe (and gr-gsm, derived from airprobe) to see broadcast, unencrypted status messages from GSM base stations. It is my understanding that other protocols (like CDMA, UMTS, HSPA, LTE) have similar unencrypted, broadcast or "beacon" traffic that could be viewed the same way ... But there are no tools like airprobe for CDMA or 3G or LTE ... why is that ? Is there a technical reason that they are much more difficult, or has it just not been done yet out of lack of interest ? Thank you.