In the past, laminated glass was usually installed in the windshield, with side and rear windows being tempered only.
The difference is that tempered glass is per-stressed so that when it cracks, it shatters into many tiny and dull pieces. Laminated is the same thing, but with layers of plastic sandwiched with layers of tempered glass. Laminated glass will still shatter, but will be held together by the plastic layers.
In an emergency, small improvised, or purpose built tools meant to shatter tempered glass will be useless if the glass is laminated.
Why would I willingly give up my ability to help myself? Roadside assistance is great, but relying on it being available is foolhardy. If you only ever drive in the city you live and work in, sure I guess. I don’t trips of 40+ miles are that unusual though.
I’ve already explained why many or most people would willingly give up their ability to help themselves. Why you in particular might choose (or not) to do so isn’t relevant as to whether it’s something that should be designed into and sold with every vehicle on the road. If I have a flat then, depending on the situation, I’m likely to change it out. My mom? Not so much. In fact, most of the people I know would be scared to try it.
As I clearly said, you are free to buy your own spare. Most people rarely leave metropolitan areas and, when they do, they are usually on main arteries with lots of nearby infrastructure.
From a risk perspective, it’s a whole lot more dangerous to drive without a good first aid kit, blankets, and water. If anything, that’s what should come standard and be refreshed as regular maintenance.