A Spiritual Successor is a type of sequel that is not part of the same world or story as its predecessor, but is nonetheless considered to be a successor because it shares common themes, styles, and elements. In other words, it’s a sequel “in spirit”.
I was thinking about how Bioshock is considered a spiritual successor to System Shock 2, went down a rabbit hole, and came across this list.
Yeah, absolutely right. “X is like a new part of Y” must make sense for being a successor. Nobody will say “Last of Us is just like Uncharted IV”!