Understand that the 1970 thru mid 1980s were HELL on the RV industry. The fuel crisis of the early 70s killed off all the tow vehicles...period. Even pickup trucks were way underpowered. During those years, A/S did introduce in the Argosy lineup a lightweight narrower trailer, the Minuet. Interestingly enough they actually made a VERY limited number of the same 6meter(20') in A/S attire (only a 100 or so built). These were really bad years that killed off most of the manufacturers and almost did in A/S. A/S was just about dead when the two guys bought it and started setting it back onto a profitable track (Thor Industries). Thor was formed AROUND Airstream as it was the first of many acquisitions that they did over the next 20 years (bought A/S in '81) and they are now the most profitable RV manufacturer in the industry. So, why so few Bambi...well remember during the years that they were made, cars had HUGE 400cu in V8s and steel frame construction. They could haul the big trailers and so the bigger ones were more popular. Then the gas crisis and the downsizing of Detroit and suddenly not even the smallest RV could be towed with a car and trucks were not much better. A/S scaled way back on models and even experimented with box type construction (granted it was composite honeycomb structural material...very expensive), but nothing helped sales. Airstream as many others turned to motorhome and coach designs as these could be designed with appropriate powertrains (although some will argue they were underpowered).
So the Bambi is just NOW finding its place in the limelight. A whole new generation is discovering the RV experience and A/Ss in particular and the little Bambi seems to really be ringing true.