It isn't terribly difficult to discern. You see, in the feudal systems of the Middle Ages, serfs owed allegiance to their lord. Kinda like "I pledge allegiance..." They also had to pay property taxes, umm rent, to that lord for being allowed to stay on the land. No matter if they built the house, tilled the land, dug the well; the land was his, and they were reminded of that when property taxes came due. But in addition to that, they paid him a sizable portion of their produce as a kind of income tax as well.
Now you might say "I have the deed to my land, it's mine, darn it." Sure. Stop paying your property taxes and see who really owns it. You might think you've earned your paycheck fair and square. But the lord has first rights to that money. He will take his portion first, and then some if you let him (interest free). Don't want to pay? No problem, debtor's prison has a nice warm cell for you.
Little about our tax system is functionally different from 12th century England.
I don’t like property taxes either. But I asked why you think income tax is feudalism. Then you explained why property tax is feudalism.