> isn't it the longest continuous democracy alive right now?

It is the one the most at risk of ending right now.

> Thy're not immune to deadlock either - sometimes going months or even a year or two to form a valid governing coalition.

It is unrelated claim, but they do have better solution for that particular problem. The governmental shutdown seem to be about the most easy to abuse way to do it.

I think they do have large problems too. And they may fall too, AfD won local elections after all. It is dubious whether Orban run Hungary was really democracy and electoral system was not reformed yet. But in this very moment, the one crumbling and dismantling itself the fastest is not UK nor in Europe.