You're right - It wasn't the RAF at 90, neither was it a comprehensive history of the RAF. I think the "snapshots" they gave were the thinking behind the development of Air Power and the effect those developments had on crews. If that was the aim then the programme probably succeeded, although there was no comparison between how a modern "bomber" force operates and the WW2 bomber raids given such a lot of coverage. They (whoever "they" are) could, however, have made several far better programmes. How about a history which included technology - changes in airframes, radar, jet engines, AAR, VSTOL.....etc or a portrait of the RAF today featuring not just pilots?
An interesting documentary, perhaps, but all in all a missed opportunity.