Probably because the horse has bolted really. The mistakes now can't be reversed. Also I think a lot of the alternative solutions are implicit in the criticism, like if people are saying government messaging is too vague then the solution, clearer messaging, is already implied.
A list of alternatives that it's not too late to implement anyway.
Copy the South Korean Test, Trace, Contain model Reverse the recent lifting of restrictions Reduce the influence on UK politics of Dominic Cummings Reduce the influence on UK politics of the US Iron out inconsistency in restrictions Stronger lockdown measures Lengthier lockdown measures Government to stop contradicting itself about the virus Stricter enforcement by police