"Besides, how is cutting tax revenues going to help fund the extra costs of fighting this pandemic in the first place?"
It doesn't. They're two separate things. Right now he's bugging the Feds because he needs to artificially prop up the economy (again) so a recession doesn't kick him in the butt before the election. (He's been warned it's coming)
A combination of a recession and a pandemic exposing his non-existent leadership would be a re-election death knell.
A pandemic, of course, is just another threat to Trump's artificial economy. "Fighting" it would be an admission that it exists and so far Trump's course of action is denial. Truth be known, having shut down all government agencies capable of preventing the pandemic, he's cut himself off at the pass. All he can do now is put a gag order on everybody and hope the denials keep his base stupefied long enough to re-elect him in November.
The fly in that ointment is that State agencies are not controlled by any such gag order so the number of cases, state by state, will get out to the media anyway.
The other fly and a much bigger threat to Trump's artificial economy is the potential shut-down of schools, businesses, transportation, interstate commerce, international trade, tourism, construction, the postal services and any other thing or place that requires personal interaction with the public, including the handling of paper money.
The very worst case scenario, of course, would be martial law when all else has failed. Then we'd have Trump's Law.