Several studies have reported that the structural axes or polarization angles of radio-loud AGN and quasars appear coherently aligned over hundreds of megaparsecs, and that radio-source dipoles can exceed the amplitude expected purely from our motion inferred from the CMB (Hutsemékers et al. 2005; Tiwari & Jain 2015). Such large-scale preferred directions and alignments sit uneasily with the ΛCDM assumption of statistical isotropy on large scales, raising questions about whether they are due to unknown systematics, unusual large-scale structure, or genuinely new physics beyond the standard cosmological principle (Blinov et al. 2020; Secrest et al. 2021).