I think there is a huge difference between clip/recap episodes, non-source material filler episodes, and episodes in an original story that are not part of driving the plot directly but exploring some aspect of a character or concept.

I think 1 and 3 are perhaps not seen as much in many shows these days as a result of tighter budgets and shorter seasons produced by/for streaming services, and it's a great shame in the case of 3 - though as someone else pointed out, some shows like Stargate SG-1 did sometimes use it's clip episodes to reasonable effect. Case 2, well...the best we can hope for is that they don't suck and don't go on so long as to kill the show.