Fortunately, the switch to color also meant an end to deleting episodes. Doctor Who was not the only program mauled by this, of coure. The famous program "Vision On" lost a huge swath of episodes from before color started up, for instance. (For those who didn't get the luck of seeing this growing up, it was an art program aimed at working as well for deaf children as others, so there's background and incidental music, but no essential gialog, although some presenters do talk a bit. This cycles back to Doctor Who because one presenter who notably did speak, and speak intelligibly, was Sylvester McCoy, who went on to play the Seventh Doctor years later. And, for those familiar with his quirks, he did play the spoons on both programs. So far as I know, the only hing he's done where he didn't get to play the spoons onscreen was "The Hobbit".)
I am a bit surprised the BBC was willing to spring for the extra costs of doing an entire adventure on film. Film is expensive, even if you only have to pay incremental costs of using more of it. (It was also already in color, so the camera operators didn't have an excuse to call for more money.)
If you want to take a look at a plausible future for the UK had there not been Thatcher, have a look at the final Quatermass series. (The UK is well down the road of Venuzuela, but without a strongman figure running everything into the ground, it all just sort of drifted that way without anyone really doing anything one way or another.)
I am a bit surprised the BBC was willing to spring for the extra costs of doing an entire adventure on film. Film is expensive, even if you only have to pay incremental costs of using more of it. (It was also already in color, so the camera operators didn't have an excuse to call for more money.)
If you want to take a look at a plausible future for the UK had there not been Thatcher, have a look at the final Quatermass series. (The UK is well down the road of Venuzuela, but without a strongman figure running everything into the ground, it all just sort of drifted that way without anyone really doing anything one way or another.)