If a market is in equilibrium is it necessarily true that all potential buyers and sellers are satisfied with the market price?

The correct answer is "no"

Explanation:

A market equilibrium occurs in those markets where consumer demand is equal to the amount offered by companies. But they don't necessarily have to be satisfied with the market price.

For example, if a product of basic need is in high demand, the price can be raised a lot which may not result in a fair price for the customer.

On the contrary, a low price on products puts potential competitors out of the market since many times due to production costs they cannot match these prices.