Some form of DNA, RNA, and proteins are all technically inevitable because they're just polymers built up of standard monomers just like complex carbohydrates,

Some form of DNA, RNA, and proteins are all technically inevitable because they're just polymers built up of standard monomers just like complex carbohydrates, fiber, plastics, waxes, etc. It's just an accident of history that carbon based life on earth settled on the specific nucleotides and amino acids. What's likely to be the most different is the transcription and translation machinery. On the nucleotide side there are synthetic creations like Hachimoji DNA [1] and xDNA [2] and a grand total of over 500 (!) amino acids have been found in nature but only 22 are encoded in DNA. IIRC it's mostly a question of the initial conditions on Earth, specifically the acidity and temperature that decides the possible chemistry available to evolving life. [1] https://en.wikipedia.org/wiki/Hachimoji_DNA https://en.wikipedia.org/wiki/Hachimoji_DNA [2] https://en.wikipedia.org/wiki/XDNA https://en.wikipedia.org/wiki/XDNA