I think there's less to this than meets the eye.
Previously, on https://sustainability.google/operating-sustainably/:
"We've set a goal to achieve net-zero emissions across all of our operations and value chain by 2030." and, in a table later, "Reduce 50% of our combined Scope 1, 2 (market-based), and 3 absolute emissions by 2030. Invest in nature-based and technology-based carbon removal solutions to neutralize our remaining emissions." and "Run on 24/7 carbon-free energy on every grid where we operate by 2030."
Now, in their 2025 Environmental Report at https://sustainability.google/reports/google-2025-environmen...:
"We aim to run on 24/7 carbon-free energy on every grid where we operate by 2030." and "We aim to reduce absolute, combined scope 1, 2 (market-based), and 3 emissions by 50% from a 2019 base year by 2030." (They also restate the thing about "to neutralize our remaining emissions" a bit later in the document.)
Exactly the same stated goals, just written in a different place. There's more hedging around it now: they call it a "moonshot" and say that they might not manage it, but they never actually promised to do it before.