‘Then the men feared YHWH greatly, and they offered a sacrifice to YHWH, and made vows.'
And the result was that the men recognised in YHWH a God Who had to be taken into account, and they paid Him due awed reverence, and offered a sacrifice to Him, and made vows, presumably vowing to continue to honour Him in the future. This would no doubt be done once they had landed, possibly by a pilgrimage to Jerusalem. Thus Jonah, who had fled because he did not want to take the message of YHWH to foreigners, had by his actions done precisely that. Whether the men continued in the fear of YHWH we do not know. But at least they had had their opportunity.