I couldn’t either, but it’s a bigger picture thing. Probably the most significant event of my lifetime apart from 9/11.
The significant events in your life are things that directly affect YOU.
If you must pick societal events then Brexit, if you’re British, is more significant than either of the examples you’ve stated.
Also, if you’re British, why on Earth is 9/11 one the single most significant events of your life!?
And if you’re NOT British then why is the 96 year old Queen passing away the most significant moment of your life…?
A general election is more significant to you, wherever you’re from - because it will directly affect you.