donkey cheer 

Giving false support to a movement or ideology.
To be seen as shallowly virtuous without giving proper thought or appropriate analysis to a thing.
Agreeing with the mob or popular opinion without forming one’s own defense of such a position

He never had an argument for his social justice position. He followed the crowd and gave a donkey cheer at the right moments.

donkey cheer by Hugh Wards February 10, 2024