On March 4, 2017, director Joachim Rnning stated that Dead Men was only the beginning of the final adventure, implying that it would not be the last film of the franchise, and that a sixth film could be released. The post-credits scene of Dead Men shows Will Turner, Elizabeth Swann, and Davy Jones. In September 2017, producer Jerry Bruckheimer indicated that another Pirates sequel is still possible if Dead Men Tell No Tales does well in its home release. In October 2017, the sixth film was confirmed and Kaya Scodelario said that she was contracted to return. Shortly after, it was announced that Rnning is being eyed to return to direct the sequel. As of August 2018, the sixth film is still in development.

Can we conclude that is pirates of the caribbean 5 the last one?
no