There’s a recent tradition that each new Conservative Prime Minister gets to help design their own special lectern to deliver speeches from. They cost £2000-£4000 to make; a lucrative business in recent times I guess.
It seems like they’re usually supposed to convey a certain something the PM wants to project. David Cameron’s was supposed to look statesmanlike. Theresa May’s was designed to look feminine. Boris Johnson’s was a bit bulkier in order to cope with him thumping it during his more rousing speeches.
I’m not sure of the intent behind Liz Truss' twisty one, but it’s often described as looking like a game of Jenga. Based on Wikipedia’s description of that game as involving “creating a progressively more unstable structure” this seems apt.
The version of it that was used for speeches in the Conservative HQ is predictably covered in Union Jack designs.
Poor Rishi Sunak was appointed in such a hurry that there wasn’t time for him to design his own one. He’s ended up with a straight edition of Liz Truss’s one that had been created “just in case”. In case of exactly what I’m not sure, but, hey, it turned out to be useful after all.