I don’t think it is (though Dems seem to pull that often). Supreme Court Justices seem to have a very hard time letting go of the power, even on the more progressive side (Notorious R.B.G. being the most recent example). There’s basically no way to remove a supreme court justice, impeachment will pretty much never happen. I think it’s more recognizing that multiple who are 75 years old in a stressful job and being targeted by the public more and more is likely to lead to at least one of them leaving, be it death or retirement.
Hey, some of us smart people can’t do that basic math either 😭
(In my case, calculus and ADHD combined powers to make me useless with actual numbers, real and imaginary, lol)