How to handle opposition as a scrum master?

How is opposition to the scrum frame work handled in your teams?

As a scrum master I am part of an innovation lab that leads several projects.My team includes very motivated people with +20 years of experience. I can honestly say that these profiles are high performance people. It's really great to work with a team like this.

Nevertheless, I get feedback from them that the agile scrum framework feels a bit childish and task-oriented.

As a scrum master i honestly believe its my task to provide a framework that improves efficiency and effectiviness. Wheiter it is called agile scrum or something else. Therefore the following question : do you guys have experience in a more looser framework than agile scrum? Or any experience in adapting the model according team dynamics? Thanks