Actaea

By the way, I've always been curious if there are issues that can really significantly change a country, like, say, revolutions or major reforms, after which the indicators can change dramatically and so on?

It's better not to even think about such things. A long time ago, I received an issue about the tax code of my country. I don't remember the specifics, but it was explained that it was too complicated, inconvenient, and so on. There were only three answer options. One suggested abolishing the tax code and said that this would solve all the problems. The second suggested cutting the budget for healthcare, education, and so on. The third was also on the same topic; I don't remember exactly what it was, but the essence was, again, cutting the budget. There were no other options, and since I didn't want to dismiss the issue, I chose the first option. What was the result?
The economy fell by 32 points, and taxes were reduced to almost zero. Not such a big effect, as you might think, right? But if you look at the detailed analysis of the country, everything turned out to be much worse (not long before these events, I made records of all the indicators, so I could compare them afterward)
Defense Forces: 313 -> 3
Eco-friendliness: 105 -> 37
Employment: 245 -> 122
Environmental Beauty: 217 -> 71
Human Development Index: 82 -> 52
Income Equality: 111 -> 91
Intelligence: 24 -> 22
Law Enforcement: 273 -> 1
Lifespan: 29 -> 19
Healthcare: 158 -> 10
Public Transport: 102 -> 5
Safety: 581 -> 176
Stupidity: 9 -> 14
Welfare: 94 -> 12
There were other changes, but I can't accurately recall them now. All in all, there was no good option in this issue, and the moral of the story is: sometimes it's better to dismiss it.