Best practices for handling large asset catalogs in simulation games?

I’m working on a mobile sandbox/simulation project and trying to optimize how the app loads and handles a massive catalog of local assets (furniture, characters, map textures).

I’ve been analyzing how popular games handle this. For instance, if you look at a fully unlocked Toca Boca game setup, the game has to instantly render hundreds of unique room layouts and thousands of interactive items simultaneously without massive frame drops.

Does anyone know if games like this dynamically stream these assets from a local database as the player scrolls, or is everything pre-cached into the RAM on scene load? I want to make sure my asset management system doesn't cause memory leaks on lower-end Android devices.