The goal of taxing the rich isn't to save the enormous defecit. It's to make sure they can't buy elections and undermine democracy.
It also does help to reign in some spending. Because a lot of spending is indirectly performed through subsidies. Oftentimes in the modern day for the rich who can already afford such initiatives.
The question in the GP comment was:
> What's wrong with taxing the rich to maintain current spending?
Perhaps you have something more sensible in mind, but much of this pressure is clearly coming from the perspective that we could have incredible government spending with no tradeoffs or inflation if only we summoned the political will to fight billionaires.