The simple answer is that media exposure of senior officers is heavily controlled by DGMC (Nick Gurr), under Ministerial direction. All public presentations given by 2* and above have to be vetted via a MINSUB. Similarly you don't see PUS of other Government Departments speaking out, either. That is left to the PPS or the Ministers responsible. Neither the Chief Executive of Loamshire County Council or the leader of Slagston Borough Council have these restrictions.
Recently a Station Commander was interviewed on TV about the impact of one particular SDSR cut and he gave, in my opinion, a cogent, sensible reply. He also got into deep poo as a result for speaking out on a Defence matter, rather than on a sS issue.