Nobody "subjectively" consider anything to be spam. It is spam because block space is being used for things that are not related to "A Peer-to-Peer Electronic Cash System". This is Satoshi's description of what the system is, and introducing ways to inject more data into the blockchain for a variety of purposes will dimm the main purpose down until its just another shitcoin that only big companies can afford to run nodes.
Well , seems that you only read the title and not the whole whitepaper . Look at references 3 and 4 , satoshi pointed that there are things that can be done through script , infact he was the first to inject arbitrary data on chain .