Strong gravitational lensing of distant quasars by intervening galaxies produces multiple images with measurable time delays between them, which can be used to infer the Hubble constant. However, measurements of H0 from lensing time delays show systematic tensions with both CMB-derived values and some local distance ladder measurements, and the derived values are sensitive to assumptions about the lens mass distribution, line-of-sight structure, and the cosmological model used to convert time delays into distances. The Lambda-CDM framework struggles to reconcile these measurements because the method depends on accurate mass modeling of the lens galaxy and its environment, where dark matter distribution assumptions and degeneracies between model parameters introduce systematic uncertainties (Suyu et al. 2017; Wong et al. 2020).