What made this game special for me was the humor, plus the story and relationships were really well intertwined! Other AVNs suffer from mainly consisting of "dates" where nothing really remarkable happens. In OIALT you get dates in your story segments and story segments in your dates; not once was I bored. And at the end of it all you feel like you really bonded with the characters that joined you on your journey, and the (best) ending was really sweet. Though I agree with the moral concerns you have, I didn't like that part either.
Eternum might overshadow OIALT, especially once it's finished as well, but to this day I haven't seen a finished AVN better than OIALT. As for graphics and music: Yeah, it's noticable how Caribdis got better and better while he developed the game. The beginning can be indeed quite rough for spoiled AVN consumers ;)
I think you judge by the standards of now against what the world was tech-wise when the game was created. Yeah, the division of character traits is better in Eternum, and there is less squick (even accounting for hosting rules imposed during development) but I find your critique of little merit.
This game is evolutionarily relevant. If you know of a finished game even remotely similar that is even half this good, please share with the class, as all of us would love to play it. If you don't get WHY this game appeals to people (which seems likely, given the wording of the critique) even across non-appearing kinks, then you just don't get it, and never will. And that's fine, but don't undermine the game.
OIALT was Carbdis' first game right? I'd view it as his skills developing over time then, especially if you're comparing it to Eternum. You can even see his skills develop in OIALT. The lighting changes, the scenes get longer and better, environments become more unique, etc, etc. Especially the scenes and lighting.
Eternum was made using everything he's learned from OIALT. And from what little I've played of Eternum so far, he's learned a LOT (Eternum's been pretty good so far, definitely an improvement)