Deus Ex? What concepts are novel? It came out in 2000, Shockwave Rider came out in 1975, Neuromancer in 1984...
Your original question wasn't about novel concepts, your original question was about speculative science fiction that a 20+ year old video game portrayed which has since come true.
Deus Ex (released in 2000) included these concepts that since have come true: Mass surveillance via global eavesdropping systems and data-mining algorithms (ECHELON-style interception, automated profiling, and "surveillance AIs"). Algorithmic profiling that anticipates social networks' surveillance-capitalism dynamics (people trading privacy for visibility, data-driven identity inference). Ubiquitous facial recognition/biometrics and AI creeping into daily life as decision-augmentation rather than humanoid robots. Symbolic, media-amplified terrorism targeting landmarks and public perception (terror as theater in the 21st century). Domestic terror threats and biosecurity fears shaping policy and policing. Elite capture of critical infrastructure and information channels (private power influencing global communications/governance). Cyberwarfare and hacking as routine tools of state and non-state conflict. Conspiracy-enabled misinformation ecosystems flourishing online. Pandemic/biothreat anxieties normalizing emergency powers and securitized public health. Drone-style remote operations and privatized paramilitary/security forces. And "the grey death" disease was basically COVID.
>What media could you recommend that touches upon AI being used to filter content as a control mechanism by the elites before 1999
The Shockwave Rider (John Brunner, 1975) — Early vision of algorithmic profiling and elite-controlled data networks used to shape public perception.
This Perfect Day (Ira Levin, 1970) — Central supercomputer curates and censors all available information to maintain social control.
Snow Crash (Neal Stephenson, 1992) — Corporate/elite-driven control of digital media and information through algorithms and virtual spaces.
Brazil (1985) — Computerized bureaucracy alters, suppresses, and "corrects" records to shape reality.
The Matrix (1999) — AI constructs a total reality filter, controlling what humans can perceive and "know."
>the specific reference to Internet becoming what it is today in particular
EM Forster's
The Machine Stops (1909) depicts a globally networked society where individuals live in isolation, communicate via instant audiovisual links, rely on a centralized information repository, and consume algorithmically mediated lectures and messages—anticipating video calls, online lectures, social feeds, and platform dependence in a grounded, infrastructural way. Check it out. Also, from the 'London Times' of 1904" (Mark Twain, 1898) — He envisioned a "telelectroscope," a global communications network over wires enabling real-time viewing of distant events and public verification (a proto-livestream/webcam scenario), effectively prefiguring the social and informational functions of the modern Internet.
>nanomachines parasite approach
Achieving parasitic nanomachines would require autonomous, error-corrected self-replication using host-derived precursors (e.g., amino acids, nucleotides, lipids) via molecular mechanosynthesis or ribosome-compatible biohybrid pathways, coupled to a metabolic module that harvests chemical free energy in vivo (e.g., ATP synthase–like proton gradients, redox cycling on NAD(P)H, or catalytic use of heme/iron-sulfur clusters) to power locomotion, synthesis, and repair under physiological conditions. Yeah, we're not there yet - to my knowledge. These nanomachines would also need adaptive information processing and control at the nanoscale (e.g., embedded DNA/RNA/protein logic circuits with feedback, CRISPR-class sensors, and quorum-like communication) to implement tissue tropism, immune evasion (wacky stuff like glycan cloaking, complement control, MHC modulation), error surveillance (mismatch/oxidative damage repair), and lifecycle regulation, all within a robust materials framework (self-healing protein/DNA origami or metamaterials) that resists proteases, oxidative stress, and shear forces while maintaining biocompatible interfaces for host resource extraction. In other words the nanomachine would need to be far more biological in form and function than it is synthetic, to the point that modern technology cannot achieve to civilian access knowledge at least.
>I fell asleep once playing Death Stranding
MGS4 nearly broke my patience but I made it through that. More so out of sunk cost fallacy than actual intrigue.