The most common criticism is that the show spends roughly 60% to 70% of its runtime on Earth . While these segments explain the scientific principles behind the alien designs (like extremophiles or gravity), many viewers found them to be "filler" that distracted from the promised alien content.
The CGI is widely praised for being photo-realistic and imaginative. However, because of the high cost of animation, the show frequently recycles the same 3–5 minutes of footage multiple times per episode, which many reviewers found frustrating.
The show is noted as an excellent "entry-point" for beginners or younger audiences interested in astrobiology and evolutionary biology. More scientifically literate viewers often found the explanations "basic" or "patronizing". Alien Worlds
Reviews for the series are generally mixed, as viewers were often split on its "hybrid" format, which blends high-quality CGI alien sequences with real-world nature documentary footage. Critical Consensus
The Netflix docuseries (2020) is a speculative nature anthology that imagines life on four fictional exoplanets by applying the known laws of physics and biology on Earth. The most common criticism is that the show
“I personally enjoyed it a lot... it’s like stoner thoughts made into a TV show that actually use physics and math to theorize what could exist out there.” Reddit · r/scifi · 5 years ago
Critics and audiences highlight several recurring themes in their assessments: However, because of the high cost of animation,
Sophie Okonedo's narration is frequently cited as a highlight for its "calming and mysterious" tone. User Perspectives