Wiking were unlucky in that their new range had direct competition not just from Triang but also Hansa.
Whereas Wiking did not release any models of ships built in the 1960s Hansa stayed in production throughout the 60s and 70s.
The reason for this was the incredible popularity of Wiking's range of 1/87 plastic road vehicles. Model railways were a great father son leisure activity in prosperous Wwst Germany and no layout was complete without Wiking.
Wiking reintroduced recognition planes in 1/200 even making a Vulcan B1. But they lost out to the German firm Siku who made models in 1/250 with undercarriage so that they could be used to build a model airport.
Siku stopped selling its aircraft models in 1964 but Wiking planes and ships were still being sold with the 1961 catalogue from Argyll models in UK
As an interesting footnote the 1980s saw a new German manufacturer test the waters with MS Europe and a Hapag Lloyd containership for a couple of years.