Yeah, even ultra-fast TN gaming monitors switch 1000x slower, and they're designed to push generously past the limits of perception. I think we can safely assume it's a capture rate.
The reality is that no scope with a LCD screen as display can achieve a true display rate of anything close than 1M wfms/s, or even 10k wfms/s, not even a Keysight DSOX3000. It's simply impossible when the physical screen refresh is some fixed at 60Hz or so. What the scopes can do is to collect display data between refreshes in a buffer and then update the screen at the next refresh cycle. Which is close enough.
The waveform update rate, for which the better term would be
trigger rate, simply describes how many time per second a scope can update the waveform data in its memory. On an analog scope where the CRT phosphor acts as both, waveform memory and display memory, the display rate obviously follows the trigger rate, which could reach in excess of 600k triggers/s. Which means the trigger rate is limited by timebase (the time it takes for the beam to sweep from left to right), the trigger re-arm time, and the time for the electron beam to fly back to its initial position.
On a DSO, the trigger rate is limited by memory length (larger memory leads to longer time to complete an acquisition cycle), trigger re-arm time, and backend processing (how fast can the captured data be processed and fed to display memory) but not the display refresh rate (which, again, will stay at 60Hz or whatever it is). With modern real-time DSOs with fast ADCs which cretae large amounts of data, the limiting factor in regard to the trigger rate is the backend processing. Some digital scopes (i.e. Tektronix) have special modes where some or all analysis/measurement functionality is disabled to provide more ressources for waveform processing, leading to higher trigger rates. Keysight deals with it through its own proprietory waveform processor (MegaZoom), LeCroy through its high bandwidth architecture (X-Stream).
In regards to these Zhiyuan scopes, I pretty much doubt that they can reach anything close to 1M wfms/s, not as display updat rate nor as trigger rate.