At what point do I need multiple scenes (performance-wise)

Hi all.

Some context*:*
I’m just starting out as a beginner and I’m planning to make a game with the size of something like Stardew Valley or maybe even a game like the old-school Pokemon games. So it’s like a small town, 20-30 buildings, 30-40 NPCs with their own schedules and pathfinding.

I have this setup in a very basic scene. I have no idea how my performance is right now, but it seems to run smooth. My character textures are like 32x32 pixels, so it’s all very small. I have some NPCs that constantly calculate new paths or check if they’re on a schedule, but I can’t imagine that would be too heavy.

What I have now:
I now use just one scene for everything. I use some tricks to make this happen. For example, the indoor areas of building are all in a corner of the world, so they are not visible and when the player enters a building, I teleport the player to this location. That way, all other objects outside stay active and keep their pathfinding going. So when I exit the building again, the NPC actually moved around according his path/schedule. But when I would use multiple scenes and use a different scene for the indoor area, it would look like time froze outside while I was inside because all objects go inactive when loading another scene.

Solution?
I know in Stardew Valley, when you move from the town area to your farm, the game turns black for a second and it looks like you load into another scene, but maybe they use the same trick as I did for the indoors of buildings and teleport you to another part while secretly keeping the one scene active.

So in my experience so far, multiple scenes seem like they make it harder to manage persistent objects that should continue their path or objective and not freeze in time. I guess a second scene would make sense if you load into an entirely new area though, or when entering a cutscene or whatever. But as my game probably wont run into performance issues as it’s relatively small, keeping most stuff in the one scene seems like a good solution. What do you guys think?

This is interesting for me too.

Please don’t necro threads like this.

Thanks.