I don’t write that often about current tv, mainly because there’s a lot of it and it is mostly bad, or repeats of bad.
I grew up in the 1960s, when the UK had just two channels (later three), BBC and ITV.
It was a period of time when the UK produced some of the world’s greatest tv, regarded these days as classic cult tv. Many of the series are still shown on the cable channels. They were mostly, perhaps all, filmed on genuine film stock and have survived, and many have been restored and are available on box sets at reasonable prices.