I do not have the impression that any politician who is not about to retire, does not care about approval ratings. There is more to democracy, than voting once every 4 years.

A ruling party having a catastrophic electoral position only for it to rapidly improve as election approaches is a fairly common phenomenon in modern democracies. Most recently, Canada was in that situation. Before that, Britain several times. There are plenty of historical examples as well, Reagan and Thatcher in their first re-elections for one.

The latter would have undoubtedly faced a revolution if Britain had no elections. Later, she'd go on to become an invincible electoral juggernaut.