I still enjoy the show but if I am honest with myself, its clear to me that the show largely ran its course quite a few years ago when they were still on the BBC. They are pretty much out of ideas now and that is fine, its time to park it in the carpark for awhile and perhaps dust the format off in a decade or two with a whole new cast.
It was probably the best thing Amazon could do with it was to make it into a few annual specials to finish off the show, I think its been a fitting end.
Whoever said they want to see a return to serious car reviews (aka, the 'magazine format'), just no. It was actually boring and doesn't carry a mainstream audience large enough to make a full television production on it. That's why it was cancelled, it was the case back in 2002 when most people still had dial up or didn't even have the internet at all and is even more the case now.
As soon as you start talking about how the crease in the door panel seamlessly morphs into the rear bumper, you lose the mainstream audience. There is no demand for a show like that on TV and YouTube has pretty much become the go to place for that kind of content.
The only reason Top Gear and TGT became the success that it was is because it was morphed into an entertainment show. Even on the new home for car based content (YouTube), there is a distinct difference between the viewership of channels which focus on serious reviews and others who have more entertaining content, the latter being significantly more popular.