I honestly can't tell which part you think wasn't normal. Other people have kind of poked back at what you are saying, but I feel without really questioning which part of this you don't like, as it kind of sounds as if you are just saying "don't hang around near geysers... and, thereby, don't go to visit Yellowstone".
If you saw this same video but without the black color, would you have run? Because that would feel a bit silly to me: these kinds of explosions are happening all around you the entire time you are there. Some are even larger than this one, and you don't just stay as they happen: you sit on a bench and wait for an hour or two hoping to see it while you are there, and there are giant clocks trying to estimate when the next eruption will be.
Now like, what if the color were grey and there was mud? Some of the geysers have mud. Most of these are not a concern. What was a concern here was the black color... but as someone who has spent a bunch of time filming these geysers I found the black color so confusing that it really took me a moment to go "oh shit those are rocks". I could easily see myself having that pause we see from the other people before they all start running.
But, again: I don't feel like you are saying "these people should know rocks are dangerous" or "this was obviously different and you should be informed and on your toes ready to run"... you seem to be saying that, if you were standing somewhere and the ground suddenly exploded that you'd of course run; and, maybe that would be the absolute safest thing you could do, but then... why are you even there in the first place, if not to see an explosion of superheated steam?
Also, remember that the entire region seriously smells like sulfur and other strange gases... this is an area of terrain that people have long ago artistically (maybe even mythologically) described as the doorway to hell, between the smells, the color, the explosions, and the regions of trees that are either scorched, petrified, or merely poisoned. It honestly does make sense to question why people visit such an area in the first place, but once you decide to be there... well, it seems strange to question why you don't see everyone panicking about the explosion.
If you saw this same video but without the black color, would you have run? Because that would feel a bit silly to me: these kinds of explosions are happening all around you the entire time you are there. Some are even larger than this one, and you don't just stay as they happen: you sit on a bench and wait for an hour or two hoping to see it while you are there, and there are giant clocks trying to estimate when the next eruption will be.
Now like, what if the color were grey and there was mud? Some of the geysers have mud. Most of these are not a concern. What was a concern here was the black color... but as someone who has spent a bunch of time filming these geysers I found the black color so confusing that it really took me a moment to go "oh shit those are rocks". I could easily see myself having that pause we see from the other people before they all start running.
But, again: I don't feel like you are saying "these people should know rocks are dangerous" or "this was obviously different and you should be informed and on your toes ready to run"... you seem to be saying that, if you were standing somewhere and the ground suddenly exploded that you'd of course run; and, maybe that would be the absolute safest thing you could do, but then... why are you even there in the first place, if not to see an explosion of superheated steam?
Also, remember that the entire region seriously smells like sulfur and other strange gases... this is an area of terrain that people have long ago artistically (maybe even mythologically) described as the doorway to hell, between the smells, the color, the explosions, and the regions of trees that are either scorched, petrified, or merely poisoned. It honestly does make sense to question why people visit such an area in the first place, but once you decide to be there... well, it seems strange to question why you don't see everyone panicking about the explosion.