The last four years in the US and UK have seen events that fall under this definition. So, yes, broadly I would agree with you. There is an argument that it has always been there, but the institutions that have underpinned the UK (and US) have protected us from going fully down the ultranationalist and authoritarian route. You can watch it play it in a more extreme form in Turkey, where economic logic is replaced by nationalist/religious insanity.
Electing people like Trump and Johnson, who are happy to ignore codes of behaviour and norms, undermine these institutions as they seek to subvert them for their own ends. With Trump it culminated in an attempted coup by the sitting executive. With Johnson it cheapens and reduces them to hapless impotence.
Bottom line, we elected them so we are obliged to live with the consequences.