They are an unnecessary waste of money which is particularly short in rural areas, and merely duplicate the existing functions of local councils.
A few years ago it was decided that AONBs (Areas of Outstanding Natural Beauty) should each have some form of board, invoving a staff, website, publications, meetings, input into planning decisions etc. These were duly formed and now are staffed up and eating money and wasting time.
The planning functions can be discharged by locally elected bodies eg councils who have due regard to AONB status when looking at applications. Everything else they do is a complete waste of time including handing out tiny grants to local bodies – councils can, and do, this already. Basically they are an extra layer of non-accountable cost which duplicates council functions. No-one asked for them and no-one would miss them.