In this particular case he's not being irresponsible in terms of the actual number and the deficit.
In a situation like this, budgets do not matter and since it is the most serious issue to face the world since WWII, it only makes sense the spending would be as high, if not higher.
The issue is the structure of the spending and particularly the slush fund, typical Republicanism, save the rich, **** the poor, the Christian Conservative Way.
What he absolutely can be blamed for in the lead up to this was the ill advised tax cuts that Republicans recklessly pushed through in a time of supposed economic prosperity and Trump being so publicly frustrated with the Federal Reserve putting up interest rates in any way.
I am extremely worried about inflation and price stability depending on how long this goes on, but I do think we can spend our way out if we fight this thing aggressively and all chip in to tackle this thing in the short term, but if people act like ****ing morons and prolong it through stupidity and recklessness, than no government will be able to get a handle on this economically.
Places like Vietnam, Taiwan, Singapore and South Korea prove their is a road map to normalcy even within the context of this virus, we just have to act on it, I am uncomfortable admittedly with some of the more invasive practices some of it entails.