That makes perfect sense. I would be surprised if someone does a dedicated 1st stage recover test. After a full rocket launch, the 1st stage is spent anyway, either having it crashed somewhere or using it to test vertical landing makes no difference to the launch mission.
A 10km height flight test is already pretty full on as well.
From memory, SpaceX's F9 prototypes (grasshopper and F9 Dev1) only flew up to a max of 1km altitude by 2014 which was the last and highest hopper test that occurred, and during that period were already doing controlled descents over the ocean with first stages with Falcon 9 rockets, which culminated in the first successful landing in 2015.
It'll be interesting to see how quickly they can succeed with a ZQ-3 first stage recovery.
One difference is that while their hopper tests seem to be pushing the boundary a bit more than SpaceX's hopper tests for F9, the F9 was already conducting successful launches for a couple of years during that period alongside the hop tests