IMHO Yes,
You wont get full benefit of impact map but still a benefit.
In my case Impact Mapping is a nice tool to fight Mushroom Management
It's not about impact mapping but increasing transparency on Mushroom Management and showing incompetence of people using PowerPoint Management
For e.g. In current company when I've joined we had "business goals" like Best UX, Best UI, New Features and Cloud.
I've started by challenging for true Business goals and KPIs.
Meanwhile I've managed to setup a practice to improve transparency on Sprint Goals using Miro and Impact Mapping format
A Year has passed and We just past an actual impact mapping session with stakeholders using true business goals and KPIs