no no I guess "rendered" is the wrong word but I remember the images having better quality ya know? Maybe I'm mistaken but this is like the compressed version quality now. Like the outlines are kind of blurry and stuff? Or maybe I just remember things wrong idk.
I haven't played the latest version, played the one before it, but its been pretty high res for me, might just not be displaying right on your screen. I think if you click Ctrl G or something like that, you can change the graphics engine Renpy is using. Its helped me with other games in Windows 11, had no issues in 10 though. Could also depend on your display's resolution, playing in windowed mode might make it look better.
I do feel like I remember book 1 looking a lot more dated than the newer books, not sure where you're at in the story.
And you're using the word rendered correct, render can be used for 2D as well.