“The same beautiful trajectory of birth, change and then death is inherent in our lives. So why is death at the human level so much harder to contemplate?”
Individual life (including human) dies, but the species is trying to reach immortality; that is, your standpoint is wrong.
“The energy of the universe will be dominated by this dark energy — … The universe, then, will end not with a bang, but an exquisite arabesque, a cold pristine place devoid of all the things we know and love.”
If the Planck CMB data (dark energy = 69.2; dark matter = 25.8; and visible matter = 4.82) can be calculated with a ‘structure function’ (independent of the time), your above statement becomes total speculation (see, https://tienzengong.wordpress.com/2015/04/22/dark-energydark-mass-the-silent-truth/ ).
The battle for the finish line (the final truth, including the end-state of the universe) among different physics schools is totally hinged on one Litmus test: how to calculate the nature constants; (see https://www.linkedin.com/pulse/totally-blind-deaf-googlefacebookblogosphere-era-jeh-tween-gong ).