Pricing the invisible
The hardest thing to sell is the thing that already worked before you charged for it.
Information is invisible. Its cost is invisible. Its value is invisible until the moment you need it and it is gone.
That is why pricing content is hard. You are not charging for a thing people can hold. You are charging for the difference between knowing and not knowing, and that difference is only visible after the fact.
The honest answer is that price is a signal, not a tax. A price says "this took work, and it is worth your attention." Free says "this is marketing." Both are legitimate. Confusing the two is where publishers lose.
Set a price that respects the work, and let the price do the talking the content cannot do for itself.