Recently, Masahiro Sakurai confirmed that he is still working "full steam ahead" and has no plans to retire, while simultaneously developing an unannounced new project. The content, title, platform, and nature of this project have not been disclosed, and it should not be assumed that it is the next Super Smash Bros. game.
Masahiro Sakurai stated that as long as there is demand for his work and he possesses the ability to meet those requirements, retirement is not currently in his plans. However, he also admitted that he cannot determine how much longer he can continue working at his current intensity.
Public interest in his activities is also tied to the Super Smash Bros. series. It has been eight years since the release of Super Smash Bros. Ultimate, and a new entry in the series has yet to be officially announced. Claims that the mysterious project is "almost certainly" the next installment in the series are merely the author's speculation; Masahiro Sakurai himself has not confirmed this.
Masahiro Sakurai and his team previously took a break from the series to develop Kirby Air Riders, which was released in 2025. He has also spoken in the past about the exhaustion caused by making Super Smash Bros. Ultimate and his uncertainty about how any future title could surpass it. What is certain is that he is still working on game development and has no plans to retire.