Yeah for porn AVNs anything that's not just a story with (ideally plot-altering) choices at most is a sandbox. Things like maps, stat and money grinding, puzzles, point and clicking, minigames, etc are sandbox elements that tend to shock or break immersion. Not only that it makes things harder than necessary just to tell a porn story, both for coders (since Renpy wasn't meant for actual games when Unity is far better for that) and readers even when there's an in-game guide or walkthrough through telling you where to go next when ideally the plot automatically takes you to the next scene. In short having to think too much or repeat shit that could be handled by a series of unique choices/scenes kills my boner (ie simple yes/no's vs some hidden threshold needed of some 0-100 stat just to unlock sex with a particular LI, usually done from repeating the same monotonous scenes over and over the required number of times in the worst sandboxes).