This is incredibly nice, but I kept wondering how it looked like in real time. 6000 fps is a lot, so how much is it slowed down ? 100x ? (6000 -> 60 fps?)
Of course this doesn't help with the issue of pre-processing, but assuming no frames have been removed or interpolated the factor 200 should be more or less correct.
Problem left: at least I can't really mentally process what 200× faster/slower would look like. (Besides turning the light on tonight, opening the window and watching at moths flying into my room and taking off again...)
I guess bigger number is better click-bait?
Calling out the frame rate is a quick and easy way to tell you that you are going to be able to see some details that you ordinarily don't get to see. Yes, the higher the number the more nuanced the detail can be. They could call it HFR, but until recently 60 fps was considered HFR and not normal. So 120 fps would be HFR as much as 6k fps, but lets face it 6k fps is much more impressive than 120 fps.
I don't find it to be click-baity at all to include the frame rate in a title of a video. In fact, I find it quite useful metadata.
When the guy filming it switches his camera from 30fps to 120fps, 240fps, or 6000fps, he knows exactly what the result will be so he starts thinking of "6000fps" as a specification for how slow it is, which it isn't.