If you're not changing the tax code, you're simply extending current policy—you are not increasing the deficit. The bottom line here is that it's a $4.3 trillion tax increase, not a $4.3 trillion deficit increase.
-- Mike Crapo
Most of the tax cuts passed by Republicans during President Donald Trump’s first term, in the Tax Cuts and Jobs Act of 2017 (TCJA), which raised deficits by $1.7tn, are set to expire at the end of 2025. ... Without new legislation, current law requires tax rates to return to their pre-TCJA levels. Maintaining the current policy would cost nearly $5tn in lost revenue over the next 10 years.
-- Oren Cass
Passing economic legislation through the US Senate can by-pass the 60-vote rule if the legislation does not increase deficits beyond 10 years.
The total public debt has ballooned by over $16 trillion under the Trump tax cuts.