As long as we have values, desires, dislikes and make judgments (which all of us do and which maybe is a defining characteristic of the human being beyond the biological basics) and if we want to put these values into a logical consistent system, we have an absolute moral system.
No, we have an absolute moral system per person. You can then take groups of those moral systems and combine them, in various different ways such as simulating what they would decide if they voted. However, you will get different results depending which combining procedure you use, and what sort of people you put into the combining procedure.
Substitute "moral system" with "reality". Would you still agree with it?
Level 1: Algorithm-based Intelligence
An intelligence of level 1 acts on innate algorithms, like a bacterium that survives using inherited mechanisms.
Level 2: Goal-oriented Intelligence
An intelligence of level 2 has an innate goal. It develops and finds new algorithms to solve a problem. For example, the paperclip maximizer is a level-2 intelligence.
Level 3: Philosophical Intelligence
An intelligence of level 3 has neither any preset algorithms nor goals. It looks for goals and algorithms to achieve the goal. Ethical questions are only applicable to intelligence of level 3.