We critically examine recent claims challenging the viability of the G-step model (GSM) as a solution to the Hubble tension. The GSM proposes a $\sim 4\%$ increase in the effective gravitational constant $G_{\mathrm{eff}}$ beyond $z\approx 0.01$ to reconcile local and early-universe measurements of the Hubble constant. Through detailed quantitative analysis, we demonstrate that many proposed constraints on the model require careful reconsideration. Key findings include: (1) Modern stellar modeling indicates a weaker $L\propto G^4$ scaling rather than the traditional $G^7$, significantly reducing tension with stellar evolution constraints; (2) The fluidlike behavior of Earth 150 Myr ago preserves the day/year ratio across any $G$ transition; (3) Paleoclimate data showing $\sim 20°\mathrm{C}$ cooling over relevant timescales appears consistent with, rather than challenging, the GSM; (4) Distance indicator comparisons allow for $\mathrm{\Delta }G/G$ variations up to $\sim 20\%$ at $2\sigma$ when systematic uncertainties are properly included; (5) The discrete nature of the proposed $G$ transition preserves relative stellar population ages used in cosmic chronometry. When accounting for proper uncertainty levels in both observations and theoretical modeling, we find the GSM remains a viable candidate for resolving the Hubble tension. We identify specific observational tests with next-generation facilities that could definitively confirm or rule out the model.

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• Cosmological parameters
• Cosmology
• Dark energy
• Dark matter
• Evolution of the Universe