"Another Brick in the Mall" Engine vs Unity: Performances

Hi everyone,

The game “Another Brick in the Mall” is a building sim game in which you are building and managing from ground up a mall. One of the feature is to be able to completely zoom out and display the whole map in its entirety, which represents exactly, 512 x 288 tiles of 64 x 64 pixels, a total of 147456 displayed at once on screen.

On my machine, the game never drops below the 150 fps.
On this thread, the developer explains that the engine is tailored made to support this (on the top of an impressive amount of cars and people moving around, doing a lot of path-finding, and so on).

I tried to reproduce the same idea with a tile being a GameObject in Unity, with one single texture of 64x64.
Performance were absolutely awful, totally drops at 8.5 fps.

Now I presume there are better ways to handle this when it comes to simply displaying the whole map.
Please pardon my ignorance but how would one go by to reproduce this same concept in Unity?

Cities Skylines is made with unity, so certainly there are ways to show lots of objects…

At least look into tilemaps, spritesheets (so that no need to have individual gameobjects and your sprites get batched together)