Anything from the Natural World unit is second-to-none. Green Planet, Asia, Wild Isles, etc are all gob smacking.

I didn't realize it was this bad. Though, the last British TV show I consumed was Dr. Who, and I quit watching about the time Capaldi took the stage.

I cannot think of another show that I've watched... There was a David Tennant murder mystery show that was quite dark, but I didn't finish that one, either.

If you want quality it takes time and focus. Given how much content there is and how little free time we all have, the fact that traditional British TV shows stop when they're good rather than running any successful show into the ground is a point in their favour IMO.