Why will inflation raise sellers' purchasing power?
One price relative to others
The key parts of the statement &quot;When a price rises, buyers of that good must pay more, but sellers get more revenue when they sell it. The loss in buyers' purchasing power is matched by the rise in sellers' purchasing power.&quot; are &quot;a price&quot; and &quot;that good&quot;.
If the price of oranges increases from \$1 to \$2, then it does not imply that 2 dollars post-inflation is worth the same as 1 dollar before the price rise; we could expect some devaluation, but it would be proportional to the impact of oranges in the whole economy.
Oranges increasing in price means that the purchasing power of people who buy oranges is decreased, but the purchasing power of people who sell oranges is increased, since they can buy more stuff (e.g. apples) from their orange-derived revenue than before.