Ignore those messages from
ebay. They are bogus AF. I see them as both a seller and a buyer. The messages to buyers always suggest making a higher offer, and the messages to sellers always suggest pricing items lower or making lower counteroffers.
Those messages are created by
ebay for the benefit of...
ebay. Period. They do not have buyers' or sellers' best interests at heart, only their bottom line, so their algorithms will recommend ANYTHING to increase the likelihood of a sale.
Offer what you feel appropriate, regardless of what
ebay recommends.