If you stop to think about it, there are only 3 possibilities: 1) Taxes are perfectly calibrated to exactly what they need to be. 2) Taxes are less than they need to be. 3) Taxes are more than they need to be.
Perfect calibration is nearly impossible. So that leaves 2 and 3. Which do you think is more likely of a corruption-prone organization that takes income through the implicit threat of physical violence?
The proof is there and it's called the annual budget of the country. As far as I know it's public information, not that anyone ever bothers to look at it (and rightfully so - we are paying via taxes people to look at it, and another group of people to control it).
Now that we have the question, how to we decide the answer? I think there are several possibilities, but one that comes to mind is happiness. A subjective and flawed metric to be sure, but a metric all the same.
Thankfully, we do not have to resign ourselves to thought experiments with no opportunity for real data collection, as in "Would the average US citizen be happier or less happy if taxes were 10% lower?" We don't even have to settle for logical exercises such as you pose here: "What is more likely, that corruption inevitably makes more government worse than less government, or vice versa?"
Instead, we can examine the beautifully diverse set of data-rich, large scale experiments known as sovereign nations to find how well taxation correlates to happiness.
And voila, your criticism of the article is an argument in favor of the article.
I never criticized the article, which is about social safety net and child happiness. I'm criticizing the claimed taxation level required to have nice things.
Wasteful/not wasteful is mostly orthogonal to high/low. If high taxes, in a wasteful system, results in happy people, then that means you can get the same result for less. Meaning people get the same benefits, while keeping more income. Or more benefits, for the same taxes.
People seem to think that high taxes correlated to happiness is evidence of a non-wasteful government, but it's not. Happiness is not the only metric that matters. If it was, then being happy with corruption would be a virtue.