There are a couple of other points to consider with modern electronic fuel injection systems.
Spark ignition engines often use various stratified charge systems to allow leaner mixtures and higher compression without pre ignition/knocking. Spark ignition engine fuels are still designed to have poor self-ignition qualities = high Octane rating.
High speed turbocharged automotive diesels now split the injection into several stages to limit the maximum cylinder pressure, moving closer to Diesel’s original concept. This allows for an initial pilot injection which reduces the need for good self-ignition properties = high Cetane number.
Things become even more interesting when you look at the Mahle Turbulent Jet Ignition (TJI) used in F1 cars:
https://www.motorsportmagazine.com/articles/single-seaters/f1/ferraris-formula-1-jet-ignition/
Or the Homogenous Charge Compression Ignition (HCCI) Engines which are neither spark ignition nor Diesel:
https://www.intechopen.com/chapters/43660