I mean I didn't expect consistency overall, but I did expect each one to at least be consistent with the game before it. Drip is the main problem, where Blanch went from clearly being the test subject to being the person in charge of the tests.
As for the length, I did expect it to be short, but some of them just felt ridiculously so. Swell was just a clone of that agar.io type game and barely lasts long enough to develop atmosphere. 16 was just "walk into the yard and collect 3 plants". Vale you grab two books and then die. Like, I'm not asking for game of the year or anything of course, I know what to expect from game jam-types, but at the very least it should be more than "I made a single room and put some interactables in it", that's bad form. A couple of the "collect x item" games did the same thing but that's already been brought up by other people.
I agree with you about the narrative breakdown; it's clear that some of the devs wanted to try to keep a narrative thread going (like The Participants making a clear effort to refer back to Blanch, the participants and the test) while others didn't seem to make much effort to link at all (Day 11 seems to have zero connection to Organ of Eden).
I didn't really expect much from the length because I see it as a bit like the Haunted PS1 Demo Disc - more about concept and experience. 16 was one of my favourites, despite it's length, because I liked the concept of gathering herbs for a ritual: A longer game with expanded mechanics could be really cool. Likewise, Vale had really good atmosphere which made it far superior to Specimen 15 despite them being very similar in concept.