My stance on this is that both "groups" bring some compelling arguments on the table, in favor of their ideology. I don't know. I think there's a place where we draw the line. For example, nowadays, I think we've crossed that line (towards more government of course). I don't think we need that much government into the markets.
I also feel really stupid when I see politicians talking about taxing gains from cryptocurrencies, with phrases like "unhosted wallets", or by attacking privacy services. They talk as if privacy invasion is a requirement, or "obligation" as per the social contract theory. I think this really crosses the line.
To be honest, one could write a novel about whether the taxation is theft or not. My short answer would be that in a country where government cares about their citizens, does good for them, funds what's strategically important, takes care of housing, helps people to get a high quality education, helps them to start a business, helps them to expand, gives them low % credits and so on, then taxation is not a theft but does such a country exist? No. There are the good ones but not such ones.
In reality, taxation is theft but it's like, I steal it from you but I return some % to you back for improving your quality of life. Let's take Denmark, Sweden, Norway, etc... These countries offer high quality of life, when you live there, you can feel that government cares about you and your tax is not wasted but at the same time, it's not like everything is fairly done. Those who are in charge, are still corrupts and the tax that they collected from you, they use it for their own benefit, to buy penthouse, expensive cars, do some shady business deals and so on.
Taxation will always be the theft but it depends on the country. In some countries, you'll pay it because it's not absolutely stolen from you but in some other countries, taxation is totally a theft and brings back no benefit like health insurance, social welfare, unemployment insurance, etc.