The Marines jumped on it but the Navy did not since it competed against their very successful LDO program. They eventually came around and now only the AF does not have WO,s or CWO5
There are very few CWO5’s since DOD really limited the number each MOS could have. We only rated 4 W5 Marine Gunners when I retired.
They’re always messing with something. Since I was in, they got rid of all the specialist ranks except E-4.