One thing being bad doesn't mean the opposite it better. If a mixed economy, with some part of the economy controlled by the state and others by individuals, is bad, then shouldn't we go communist? If pizza with pineapple is bad, then isn't a pizza with no topping the answer?

Yes, some countries like Algeria tax 64% of the economy. But the average in the European Union is 35%, the United States has 25%. If having 1/4 less money personally (while still getting public infrastructure and benefits in return BTW) makes people ignore global poverty, will getting that money back (while no longer getting the benefits) really make them spend so much more?

We already afford to take care of our sick, and the poor across the world. It's just a question of electing leaders who actually help them. That's very hard in undemocratic states like the US, but still, it's possible. Just make sure they aren't bought with large donations from corporations and people with weatlh and economic power, because they don't care about the interests of poor people.