On the operational side of oracles, in order to keep consistency between Aave v3 and other legacy instances (v2, v2 AMM, v1), we will be creating a proposal to configure the deprecated fallback oracle address to address(0) on them.
Even if we don’t recommend doing it in the current form, this doesn’t affect any improvement/re-activation of this mechanism in the future, as it will be possible to set it up again by calling setFallbackOracle().