Public engagement on socioscientific issues is crucial to explore solutions to different crises facing humanity today. It is vital for fostering transformative change. Yet, assumptions shape whether, when and how engagement happens on a pressing issue like climate change. Here we examine three dominant assumptions—engaging the public involves power-sharing and not just information, investing in relationships can lead to mutually desirable outcomes, and more interaction is better to support engagement in climate change governance. Furthermore, we explore the implications of these assumptions and related contradictions. We offer insights to stimulate discussion on the need to understand, assess and revise implicit assumptions that might undermine the capacity to transform public engagement on climate change.