CMB measurements from COBE, WMAP, and Planck show that the largest angular scales (multipoles l?30) have less temperature fluctuation power than predicted by the best-fit ΛCDM model calibrated on smaller scales, including a notably low quadrupole and a suppressed two-point correlation above about 60 degrees (Bennett et al. 2013; Planck Collaboration VII 2020). While the statistical significance is modest and subject to cosmic variance, the persistent lack of large-scale power and related anomalies are difficult to attribute to simple foregrounds or noise, and often require fine-tuned inflationary initial conditions or non-standard pre-inflationary physics if one insists on the standard hot Big Bang plus single-field inflation framework (Contaldi et al. 2003; Boyle & Steinhardt 2008).