I have Amazon TV on my TV but it's very juddery. High Castle is fine but Grand Tour flickers all over the place.
Grand Tour series 1 was 24p, same frame rate as High Castle.
Grand Tour series 2 onwards is 25p (as is most European content on Amazon and Netflix - including The Crown)
If your Smart TV runs at a fixed 60Hz refresh rate (which many do) you will see far more judder on 25p content than 24p (where 3:2 will be used which is less noticeable to many)
It's one reason why using an external device for OTT streaming (IF it supports dynamic frame rate switching) still makes sense for many.
Also the studio elements of Grand Tour have some quite fast camera moves that expose the poor motion rendition of 24/25p capture. (Top Gear uses 50Hz for 'studio' elements, giving twice the number of images per second and much more fluid motion. Only a couple of Netflix test sequences seem to run at >30Hz, and I've not seen any Amazon content at >30Hz)
European TV content is usually shot at 25Hz or 50Hz.
US TV content is usually shot at 24Hz, 30Hz or 60Hz. (Technically 23.976, 29.97 and 59.94Hz)
Movies are almost universally shot at 24 or 23.976Hz.