I don't think things were being handled, we were just going through a cycle of spikes and lockdowns.
A lot of people didn't follow the rules because the government gave unclear or contradictory advice.
The Cummings thing did make a difference and that was the governments fault. If he had been sacked immediately, it sends a clear message to the public that this kind of behaviour isn't acceptable, that it endangers lives. Instead, they chose to cover for him, sending the message that the rules aren't actually that serious, that breaking them isn't so bad afterall. A large part of this is effectively communicating with the public, and they bungled that.
There are also a lot of people who broke the rules because they had to.
If you are told you have to self isolate, but get no support for doing so, it puts people who can't work from home in a dilemma. If self isolating means losing earnings when you are barely making ends meet, a lot of people are going to chose not to simply to put food on the table.
They are to blame for failing to make the public take this seriously enough.
They are to blame for leaving borders open and allowing reinfection from abroad.
They are to blame for the absolute shambles that was made of test and trace.
They are to blame for not supporting and enforcing self isolation.
They are to blame for going for treating this like a flu and letting it run through the populace, rather than take the extermination model which let other countries return to normalcy months ago. You don't get any new variants coming out of South Korea, or New Zealand, because they took stern measures and wiped it out. The new variant is a symptom of the governments failures, not an excuse for them.