The movie was made to play in Peoria, so it was written with a Cartesian conceit of "replicants" as others in the Baudrillard sense of simulacra: the story was designed to reinforce the idea that humanity is a stable fixed point of reference upon which cleverly designed machines are intruding. This was calculated to be assimilated my audiences (the movie functions as a memory implant) who are upon arrival to the theater were already operating under the delusion of thinking they're free because they have endless choices for consumption, including which movie to watch. The love story between Deckard and Rachel seems calculated as a somatic device to inhibit introspection that might further trouble and arouse viewers to the point of rejecting a challenging product.
My recollection of Deckard in the novel was that he wasn't much concerned with what constituted androids outside of narrow technical dimensions—though maybe I mis-recall my own reading? The character had his own problems. He was quintessentially American, preoccupied with status, possessions, work-a-day worries, televangelism, and somatic distractions, like the mood organ.
Stepping up a level, the open question of the story being who is building us as the robots we find ourselves to be? Of course there's no answer to this question: it begs a god a patriarchy, an orthodoxy.
That the movie took on a adoring following which is overly invested in particulars is typically ignorant fan fetish: Robots (fans) touching robots for pleasure. The cusp is the awareness that civilization is robotic.
Lucas's THX 1138 seems well informed by the ideas of PKD's Androids.
The uncanny and nihilistic aspect of the beast-machine was the central theme of Kubrick's 2001; the monolith illustrating a realm of authenticity inaccessible to us, no matter the power and complexity of the garments we attire as tribute to our uncanny of our self awareness. Kubrick's epic comes off as a depressive's longing for an extinction event that would result in a rebirth of the species (self) on some other plane of existence.
Tarkovsky's adaptation of Lem's Solaris tried to go further than Kubrick, with the observation that everything we feel is real is a regress of a universal mind, and our views of ourselves play out in some kind of Klein bottle of nature.
Blade Runner feels trite, but I truly enjoyed Villeneuve's sequel as just stomping ahead with the pre-suppositions of Scott's movie and continuing to build out its world of increasing alienation with some kind of an attractor of family and self-sacrifice in the midst of a gruesomely overdeveloped world: the star child has no immune system and so must live in a hygienic bubble with nothing to do but create memories for everyone else.
21st century Hollywood eating itself.