To what extent is the power of the British Prime Minister limited by the cabinet?

In recent decades, the changing management of the cabinet by the Prime Minister has led to the restraining power of the institution to be reduced. By holding smaller 'kitchen' cabinets, or getting ministers onside before holding a full cabinet meeting, disagreement with the PM's positions in full, discursive cabinet meetings can be avoided. With Blair using bilateral meetings, as well as Cameron using 'Quad' cabinet meetings of four members, the wider cabinet has been reduced to a rubber-stamping institution and holds no impact on the ability of the PM to pass legislation effectively. Despite this, should the PM have divided factions among their party leading to their unpopularity, keeping cabinet on their side may avoid them being deposed. Given the ability of the cabinet to remove the PM, and the fact that as senior party members they may hold sway over the differing wings of the party, the PM may have to seek consensus at a cabinet level in order to hold on to their job and not be voted out of office. The failure of Thatcher in the years leading up to 1990, in particular with removing Howe in 1989, to act in such a way precipitated her removal from office, a clear example of the restraining power of the cabinet to threaten a PM.