This still happens. Strange New Worlds certainly does this. A lot of drama shows I’ve followed have a “joke” episode now and then. My favorite series, Supernatural, had a handful of them (and they for some reason ended up being my favorite ones).
I agree, though SNW is not the best example, since it’s basically an affectionate homage to TOS. But yeah, it’s still a thing for sure. I probably shouldn’t have specified just 60s and 70s.
But that era is when the change in tone was most egregious. I went through a phase watching ‘Bonanza’ reruns during the pandemic. One episode featured a harrowing journey over a mountain with a couple donkeys carrying crates of nitroglycerin in wagons (for plot reasons). Very suspenseful; every bump was nerve-shattering. It was the Cartwrights and another family. One of the sons of the other family got blown to bits, and it was horrible and sad.
Then there was an episode where Hoss went into business partnership with an eccentric inventor who created a Rube Goldberg-style device to detect gold in the ground. Hoss tried to operate it, but pulled the purple flange lever too soon or something, and was caught in the middle of a huge explosion. In the aftermath his shirt and hat were torn up and his face was blackened, but other than a hangdog expression he was fine, like Elmer Fudd after tangling with Bugs. Complete with sad circusy wha-wha stinger music.
