The party out of power in any government is appropriately referred to as the “opposition” party, and for good reason. The opposition party is supposed to go against and disagree with everything and anything, if possible, that the party in power proposes or attempts to implement.
To oppose and obstruct is the logical thing for the opposition to do. There would be no need to change administrations if the opposition goes along with the party in power. The opposition does not have to propose alternatives to the majority party’s ideas but to simply suggest that those ideas are bad; there is not even a need to prove the ideas are bad.
And so there we have it: do anything, shut down the government and hope that the lack of, or poor, government service or performance enrages the people and gives them a reason to vote the ruling party out of power.