People are clearly fed up of the Tory / Labour status quo of "there's nothing we can do about the shit state of absolutely everything".
It's not complicated really is it. Not sure why people are trying to make it more than it is.
People have had enough of the traditional parties. Incumbents, left or right, are struggling everywhere.
Things have run their course. All the money has flowed to the top, as it's designed to do since Reagan & Thatcher championed neoliberalism, but there's not enough crumbs left to keep the wider population content so they look for something else. We're seeing that one of two ways. People either place the blame for the wider problems on immigrants and move towards Reform or they place the blame on the ever increasing transfer of wealth to the super rich and move towards the Greens.
IMO something radical needs to happen to move us to whatever comes next rather than a continued decline but nobody seems to have much idea as to what that next thing is.