In this verse (surah 11, verse 117) God speaks about the past in the context of some cities that were destroyed. He says if those people were righteous, then he would not have destroyed the cities unjustly.
وَمَا كَانَ رَبُّكَ لِيُهْلِكَ الْقُرَىٰ بِظُلْمٍ وَأَهْلُهَا
مُصْلِحُونَ
The conclusions you are making are problematic and your question cannot be answered. The contexts of that time and the context of today are very different.
- It is not correct to conclude that whenever a city has no reformers, that city would be destroyed.
- It is not correct to conclude that if a city has reformers, that city would not be destroyed.