The existence of money imply the existence of tax. Originally, money is a logistical tool of war, allowing kings to send armies and mercenaries to control remote regions, where they need to buy their supplies.
You, the king, give coins to the soldiers, and you tell the conquered peasants that they need to give you a certain amount of coins or you'll beat the shit out of them. Thus the peasant loser is forced to sell bread to the motherfuckers who burned and ransacked his land.
At the same time, it gives worth to the soldier's salary and justify risking their life on the battlefield.
Paying tax is a bit like giving the stick to your king so he can beat you up with it.
The social services such as fire department, hospitals, and security enforcers are hostages/pretexts for taxes, because:
1. A ruler need those services anyway, because doing without them means their territory going to shit and producing less value. What's the point of owning a house and build a family if it's gonna burn? What's the point of working hard if you just get robbed?
2. When you transpose money to anything else but military schemes, it creates the "cobra effect". It's about a story where a city wanted to get rid of cobra and gave a bounty for every snake caught. Instead of erasing the snake problem, people just bred cobra to get the bounties. To generalize it, money has a side effect of making people do anything but actual work: it's better to create problems and solve them, than actually tackle unresolved challenges. If there's a problem, it's better to be paid to treat the symptoms, than to solve the root cause that justify your pay. Public institutions are incentivized to go deficit and be wasteful to justify increasing budget. You can change internet provider if one fails to satisfy your requirements. Can you fire a policeman and hire another if you feel the street should be safer?
Like
@Tempokai said, it's all about trust. I would even say that, originally, all human transaction were based on trust. And the
Nobel Prize said that the more trustworthy institutions are, the more prosperous countries become.
If you can walk in your local institutions, and discover that everyone were hired because of family ties than actual competence, then you have the certainty that your taxes are going to shit. This can easily happen from top to bottom, like president's cousin running an institution, and they don't even care to hide it lol
To go back to OP's initial question: Tax is theft, because it's unilateral without giving you any agency on how the money is used, meaning that it could fund actual services just as it could fun corrupt parachutes, and even gambling on gacha has better rates than this
