I believe information exists without observers. A human noticed that we can burn fossil fuel to drive ourselves around instead of riding horses at some point. By that time, cars might’ve already existed for billions of years in galaxies far, far away. We just didn’t know about them. Uninventing cars wouldn’t make them go away, it will only postpone their appearance. They will reappear because they can satisfy the demand for fast transportation.

So removing inventions sounds pointless to me. Certain human behaviours or use of the inventions – sure! I’d make people commute by walking or using bicycles, for example, but I wouldn’t uninvent cars. Cars have legitimate use cases.

Same with other things like nuclear weapons or multi cookers. All of that can be described with numbers, and all numbers already exist.