What would happen with economy if in some totally fictional scenario governments decide to tax super rich greatly?

Ahh, were that to happen many hopeful futures would open up, along with some nasty ones, depending on how it plays out. The power to tax is the power to destroy. Governments inherently have that power. That is why the wealthy have been happy to pay for the political campaigns. By so doing they have assured themselves of subservient governments. The question is one of how the bottom 95% of the population gain any measure of real influence on policy. At present they are confounded by systematic mis-education and propaganda and by political kabuki theater and distracted by a myriad of salacious to outrageous but mostly irrelevant issues.

A scenario for an exit from the grip of government by the nominees of the super-rich is conceivable, if improbable. In a parliamentary form of government it is possible that a party or a coalition with a sufficient majority could decide to simultaneously turn on the wealthy who have supported them. This would be more likely were the situation very dire and the general public significantly aware that that situation was due to following policies that served the interests of the super-rich.

Perhaps a lever towards such a revolt of the MPs would be the possibility of refusing another bailout for banks and finance. Were that to happen, the super-rich would be a whole lot less rich. A charismatic popular leader who was substantially bullet-proof could, under such circumstances, lead a government that changed its policies and began policies that provided the nation with renewable energy and transportation based on same. The policies could be re-oriented towards providing widespread rising wages and reducing income inequality. There is nothing inevitable about the course we are on. It is a choice that has been made by a few wealthy people who have been able to convince enough that they are right and have prevailed.

They have created a perceived reality highly favorable to their interests and >> majority of the population view the world through that perceptual filter. It is like an evil spell and it must be broken in order that any but a very few can have a decent life. There are significant constraints due to physical constraints, but they pale in comparison to the mental restraints under which we labor.

"It is not necessary to have hope in order to persevere."