A particular word or sentence to descibe a situation
One could use take a back seat:
to choose not to be in a position of responsibility in an organization or activity
A few other closely related options could be:
pass the buck:
to blame someone or make them responsible for a problem that you should deal with
wash your hands of something:
If you wash your hands of something that you were previously responsible for, you intentionally stop being involved in it or connected with it in any way
the elephant in the room:
an obvious problem that no one wants to discuss