While the article mentions that research suggests revenue dipped in January, it's crucial to note that this is just a specific period and doesn't necessarily indicate a long-term trend or the overall health of Fortnite. The article doesn't provide a thorough analysis of the entire lifespan of Fortnite or consider other factors that could have contributed to the revenue dip.

As a result, it's difficult to draw a definitive conclusion on whether or not Fortnite has peaked solely based on the information provided in the article. To determine the long-term trajectory of Fortnite, a broader analysis of its revenue, player base, popularity trends, and other relevant metrics over a more extensive period would be necessary.