which actually doesn't make sense at all, cause eyjafjallajokull is a small volcano that happened to have it's large eruption at the right time (into this era), at a "popularized" location, while the other volcanoes with a 'generic name' are much more explosive and deadly in general. Eyjafjallajokull is largely famous because it's in Iceland and because it disrupted air travel (mostly because the winds were in the wrong directions). The last 100 years were remarkably quiet, and since Pinatubo, some can argue that we even didn't had large eruptions (VEI 6 - 7 and VEI 8 (supervolcanic) ones), which seem to be unusual, especially since we had a lot of large eruptions in the 19th century. Of course, small eruptions can have far more consequences to people, depending on the geographical location and the nature of the eruption. But the VEI 4 of Eyjafjallajokull is the largest eruption in it's history, and it erupts quite infrequently. I don't think it was even seen as one of the 10 most active volcanoes before 2010. It was quite a dark horse candidate to erupt, but it did. It's neighbour Katla is much more dangerous. Hekla - not far away either - had much more violent eruptions in the past. Grimsvotn, Bardarbunga, Oraefajokull, Askja are all example of more dangerous volcanoes, and than you also have the danger of fissure volcanoes which are often networks of underground volcano chambers. The latest large one was the one of Laki in 1783-1784 which did contribute to historically large famines in India, and it's a major contibution factor to the environmental factors that helped the French revolution to take stage. It also may have set a period of climate change, in which the period between 1780 and 1820 are among the coldest decades in the last 1000 years (partly of very low solar activity, and other very large volcanic eruptions, like Tambora in 1815 or 1816 (1816 is called the Year Without a Summer and Tambora was the largest volcanic eruption in last 1500 years at least) and an unknown volcano that erupted in 1809/1810)
And if we criticize Firaxis for being too Eurocentric / Anglocentric, maybe consider that Yellowstone is way too overhyped (has large infrequent eruptions, but there are many unknown, sometimes even undiscovered supervolcanoes on the planet. The only reason why Yellowstone is so famous is because it's in America), and I also think it's hard to implement in the game, cause it's just plain hilly areas, and resembles more of a national park that happens to have geysers in it. In game, it wouldn't be perceived as a "volcano", and in this timeline it's mostly irrelevant. It's last eruption was longer than half a million years ago (okay, there might have been some smaller ones in the last 500.000 years), but why does Yellowstone have to be included, while Toba contributed to our lack of DNA variety 72.000 years ago, while Taupo had a number of severe eruptions, while Campi Flegrei in Italy partly led to the demise of the Neanderthals and while there are volcanoes like Sakurajima (inside Aira Caldera) or Tambora out there. And those latter two ones also are easier to represent in the game. I also don't think a supervolcano that could possibly erupt would make your game fun at all. It would be a reason to restart the game for a lot of people who were doing well in their game, and it's going to be very annoying. I don't think this is the road Firaxis has to take. But if the demand is high, some modders can potentially work on it, and deliver a number of scenario's you could play: ice age world, supervolcanic eruption, asteroid impact, and potentially also extraterrestrial invasion or zombie invasions.