No argument there. The scene in the library feels insanely rushed, especially after a whole episode building up to it. It gets even weirder when Episode 5 swiftly unties the neat bow while simultaneously providing a whole new set of incompatible reasons for why the threesome didn't work if the MC is on the friendship route.
I sometimes wonder if Episode 5 was originally meant to be the end of Episode 4. Not just that DPC split the story up because it got too big, but that he intended to end the first story arc with MC/Maya/Josy in a mutually ambiguous position, the DIK mansion wrecked, and the MC getting his jacket.
When he realized he was going to have to split the story, he faced a dilemma. If he simply split the story, he would end the season by resolving the cliffhanger on an ambiguous note. But if he restructured the story to fix that new pacing, he'd have to tear up his original outline and work out a whole new structure for Episodes 5+. So he tried to split the difference: he tacked on an overly simplified resolution to the Maya & Josy drama in Episode 4 to give a relative happy ending, then turned the remaining bits of his plot into a sort of bonus episode that could patch up the loose ends while still ending where the next episode was "meant" to pick up.
I'm probably overthinking it, but it would explain why we got an Episode 5 that feels like a minimal story padded out with gratuitous sex scenes and a low-grade retcon of the M/J threesome.
I agree with you that the scene in the library is out of place as a conclusion to the first cycle.
but it cannot be said to be rushed, after MC escapes from the dormitory, Maya and Josy make up immediately, and even if we are not shown directly it is evident that they have already gone beyond the "double betrayal", Josy at least can only be aware of it since she knows what she did and can't help but realize she interrupted something. it's pretty much the same for Maya too, who can't help but know that Josy is MC's famous date when he's back home.
when they meet in the library, it is not three lovers who have to decide what to do, but there is already a couple who must decide what to do with the third wheel. in fact it is Maya and Josy who consider MC worthy or not.
MC's speech as well as being "strategically" a suicide is also completely useless, it reveals something that everyone present knows.
in the picnic scene, DPC tries to sweeten this fact by highlighting the fear of being alone, but in the library the only one who could be left alone was MC, and that wasn't a problem. and it's a bad step back, in the library they decided to stay together because they want to follow their heart, at the picnic they reveal that they have chosen this way in order not to be excluded (as Josy individually confirms in the case of refusal to MC after the scene of the father's visit)
in sentimental matters it is credible not to be very lucid, and to understand what one feels even with time, then the protagonists are objectively young and therefore it is all quite credible, but the substance is this
