2D physics lag

I have a 2d open world game (sort of) I am trying to make but I am running into one major problem: Physics lag. In the game I have 80 - 200 entities that each collide with each other and move around on the world. Is there a way to reduce this lag? The physics do not need to be complicated. Also I tried to do some of this: https://docs.unity3d.com/Manual/iphone-Optimizing-Physics.html but it only made it seem to lag more. In addition I do not want to disable the entities when they are out of the camera. I am new please make everything easy to understand.