It's optional. We don't know on whose part though. These kind of changes normally take years to implement.
Hell, the Tax Cuts and Jobs Act of 2016 didn't fully go into effect until this year (2020). IRS finally issued a redesigned Form W-4 this year that will reduce people's withholdings, but unless you started a job this year, most people still haven't filled it out.
It's optional. We don't know on whose part though. These kind of changes normally take years to implement.
Hell, the Tax Cuts and Jobs Act of 2016 didn't fully go into effect until this year (2020). IRS finally issued a redesigned Form W-4 this year that will reduce people's withholdings, but unless you started a job this year, most people still haven't filled it out.