This is because it cancels out of the equation. Biology boils down to chemistry boils down to physics and if you reduce variables on both sides of the equation, "life" is not necessary for the universe to exist. "Posits" is not the correct framing. "The Second Law of Thermodynamics requires that entropy increases over time throughout all systems in the multiverse" is accurate. There is nothing controversial, experimental or theoretical about it. If the 2nd law is wrong, everything is wrong and we fly apart into clouds of tachyons. My favorite definitions of thermo come from my 400-level thermo class, which used gambling as an analogy: : “You must play the game (zeroth law), you can't win, (first law), you can't break even (second law) and you can't quit (third law).” There's a lot of lawyerism to the laws of thermodynamics because anyone puzzling about with them is out there on beyond zebra but for normies, "time's arrow moves forward" "energy is neither created nor destroyed" "energy transfer is never 100% efficient" and "everything stops at absolute zero". Thermo don't give no fux about quantum observers. Particle or wave the gods of thermo get their cut. your part in the play changes but to the universe it's all the same. As soon as you start digging into it, all the "spooky action at a distance" schroedinger'scatism of quantum mechanics collapses into boundary conditions and framing; "energy is matter with a constant" is the theoretical physicist's way of saying "it's all just vibes, maaaan" but much like Erwin's zombie cat, pop culture turns it into something it's not. "Life" has to be defined as a thin bright line somewhere and the preponderance of the privilege for doing so belongs to the biologists. "consumes/transforms energy" has been in place since 1749 while "If I observe it I must be alive" comes from Schroedinger himself in 1944. Schroedinger, however, did not feel that the universe needed to be observed to exist but that instead, our existence is defined by our observation. While life is not typically categorized as a fundamental force, our understanding and definition of life might benefit from its thermodynamic and quantum mechanic properties.
The Second Law of thermodynamics posits that in an isolated system, entropy – a measure of disorder – invariably increases over time.