The government is borrowing a lot more after Trump’s tax cut. But that tax cut mostly went to the very rich and corporations. Both those groups for the most part just saved and invested their tax cuts, ultimately back into the US bond market. The increase in demand for loanable funds matched the increased supply, so no impact on rates.
In other words, the US government has the same spending as before, the rich and corps have the same investment and consumption as before, and rates are the same.
All that really changed is we handed rich people a bunch of bonds to get their money rather than force them through taxation.
It would have been pretty different in, say, the 70s when high rates discouraged corporate borrowing and a corporate tax cut would have led to more real investment. Likewise, a middle class tax cut in 2017 would have spurred consumption and caused rates, economic growth, and inflation to all increase.
