The point is not how long mail forwarding is good for but rather the USPS already has up to date mailing address information for US citizens.
If the IRS is using Equifax for proper address verification as the OP states, then that information is already available via the USPS which is a government agency with real oversight.
If the IRS is using Equifax for proper address verification as the OP states, then that information is already available via the USPS which is a government agency with real oversight.