If physics is the same throughout the universe and habitable worlds have similar gravity that would suggest evolution works the same throughout all galaxies, stars, planets. Meaning that humanoid aliens, or other humans would be common. But biological life is only stage 1 in the 3 stages of evolution based on my Quantum Life Hypothesis. Special relativity and evolution/physics make interstellar travel for biological life impractical and inefficient. If there are civilizations out there with interstellar travel capability then they’re likely stage 2 technological life, meaning they are machines. Meaning if we ever do make contact then they’ll likely be AI powered silicon based technological life forms. Machines. Not humanoid. I think the humanoid carbon based life forms realize that it’s impractical inefficient and too dangerous for biological life to travel between star systems. Factor in the time dilation problem that special relativity dictates and it only makes logical sense that humanoids evolve into machines for the purpose of interstellar travel. So where are they? Fermi paradox! Right? Wrong. I thing the Dark Forest hypothesis kicks in during the second stage of evolution. Look up my Quantum Life Hypothesis it explains it nicely and logically I think.