Insurance is very expensive to administer and the insurance company must make a profit.
Therefore, I self insure on as many things as possible, where the cost of being wrong is moderate (Dental, Vision, Life (in my case)).
The concept of self insurance is lost on many. They want “free” stuff.
Sure. You take your chances self insuring. We did for a few months and my wife had to go to the ER where they found she had a urinary tract infection. Cost - $1,925. But for self-paying-with-cash me, it was “only” $1,550.