I don’t understand the “Stimulus is Winding Down” argument

Kevin Hasset said, “It is no coincidence that the private sector is taking off while the government stimulus is winding down.” But the reason stimulus is so bad for the economy, according to anti-Keynesians, isn’t the spending per se, it’s the taxing and the borrowing. And as far as I know, taxes haven’t been lowered in response to the winding down and we still have to pay back all of the money we borrowed.

So, if you, dear reader, believe that the recent growth in the economy is due to the winding down of stimulus spending, what aspect of that winding down is spurring the growth? I’m not being rhetorical, I’m really asking.