Watching the rt80 event in Barking I just wondered why it was that the Routemaster bus model became the London Icon
I suppose the the routemaster is a very 'brandable' name, often people casually refer to the RT as a routemaster and I think the two are fairly indistinguishable to the average person. Also personally, I don't have any memories of using an RT day to day whereas the routemaster was a common site for most adults in London.
General combination of circumstances really -
While the 'pre war' RT bodies were built by London Transport, the chassis was something that AEC did sell (albeit in limited quantity) elsewhere - it was never quite LT's own project the way the RM was.
The launch of the RT in 1939 was quickly overshadowed by the war, and perhaps took second place in LT's publicity to the underground extensions (also delayed by the war) in the late 40s
By 1955, the RM was the new shiny thing to be shown off, even though (for various reasons, including LT finding itself with more buses than it quite knew what to do with) they didn't enter service until 1959, and by then there was the added focus of them replacing trolleybuses.
Arguably, the step change in style and technology from the late STLs to RTs was not such a big step as from RTs to RMs.
The personal memory thing is also valid - it's very much a generational thing, my dad was at secondary school by 1947, and he saw the RT and RF standardisation of the late 50s as a bit dull in comparison to the trams and pre-war generations of buses and trolleybuses that had been on the streets of SW London in the immediate post war years.
Personally, having grown up between Lewisham and Woolwich, RTs were more the standard thing on local routes until 1978.
RTs weren't quite so unique on a national scale when they were taken out of service in the 70s - half-cab buses were still around (in diminishing numbers) in most towns until around the end of the 70s / early 80s. From the early 80s onwards, London's Routemasters (or second hand examples elsewhere after deregulation) were - with a few exceptions - the only buses of that style around.
