"What happened?" are you for real?
Did you not read any newspaper, watch any news, or generally exist in society since 2016?
First you decided to bazooka yourselves in the foot with the Brexit vote, then went through a revolving clown show of increasingly bizarre political sideshow pieces that pretended to be PM, before finally opting to negotiate an EU exist that was about as disastrous as it could've been for your economy.
Add in the fact that the entire world has been turning to shit around you due to despotic leaders trying to rape their neighbours/the climate/populace/actual kids/everything joined by a cabal of evil billionaires who are gleefully destroying democracy and the world economy so they can go out in one final last hurrah of capitalism, and you have the audacity to ask "What happened?"?.
I seriously can't with these "I don't do politics" idiots anymore.