I learnt driving on British cars and european cars were all avaialble here until the early 70s basically pre 1971. GM had an assembly plant building Vauxhall Victors and American Dodge Darts, Ford were assembling the Escort, Alfa Romeo and Fiat were selling cars along with Volkswagen.
Along came Bhutto and his idiot sidekick Mubashar Hasan and they single handedly destroyed industry by putting Bureaucrats in charge by nationalising the Industry and the car industry... eg National Motors tried to build a peoples car which is the ultimate fascist fantasy.
I saw a photo of Bhutto being led around National motors being shown a " paki " designed and manufactured car... sick joke.... it was a Citroen 2CV painted by hand.... only Pakis dont know any different do they. All the discerning ones had fled the country or were thinking of leaving.
As far as the advent of Japanese cars these were certainly cheaper but the main reason for the popularity of the Japnese car was the import permit system where Bhuttos government imported Japanese cars in exchange for rice etc ( 1973 and 1977) and gave these to politicians, bureaucrats, army officers and other favourites who sold these on at a profit (The origin of the OOONNNN). All car import was basically banned in these days by prohibitive duties and tariff structures. The duty structure was regulated so that European cars.. mainly over 1300 cc in thsoe days were priced out of competition. The easing off of the import happened only in 1976 with expats being allowed cars back on TR. The policy mainly continues today.
If the Europeans had a market share and no restriction such as that stupid term DELETION they would assemble. This is why with the WTO in force and the DELETION being history you are seeing Renault and Volkswagen inetersted. As well as Mitsubishi and Mazda and Volvo. And you have Honda and Toyota shitting bricks.
As far as British makes are concerned forget JAg or Rolls ever manufactring here .....these are British makes not international ones ( although owned by Rolls and BMW)and sell because of Britishness.
The one thing that I have learnt from watching the history of the car unfold in Pakiland is that our governments are stupid only our middle class bourgeoisie are more stupid.