When I was contracting in the 80's & 90's it was basically Milwaukee or PC. When I found out Milwaukee was importing I switched to PC pretty much exclusively but they followed the same path eventually. At that time DeWalt was marketing heavily but I thought of them as Black & Decker with a paint job.
I know Porter Cable was sort of considered THE industrial brand for woodworking in the 1980s and 1990s.
Early Dewalt tools were actually really solid in most cases.
The USA made tools had been Black & Decker, but usually were the Black & Decker “Industrial” tools, that tended to be very solid, and in most cases capable of lasting decades.
The Import Dewalt tools were usually rebranded Elu tools, from the German Elu brand, which B&D had also purchased.
Elu invented the plunge router and were considered top quality. ( the DW625 plunge router from Dewalt is still basically the same Elu design, as are some other tools)
As for Bosch, some tools during the 80s and 90s were made in Switzerland or Germany, but a lot of others were made in the USA.
Bosch had actually purchased Stanley’s Power Tools division around 1980, and supposedly a bunch of the tools Bosch came out with in the next teo decades might have been based on Stanley R&D, although I can’t be certain.
I know Stanley made High Frequency motors and tools for industrial use, and Bosch still has a high frequency tool division as part of its separate industrial tool division.
Most of the USA made Bosch tools seemed to be just as solid as the Porter Cable tools.
As for Milwaukee, the imported tools that were made in Europe were usually made by AEG, and were very solid. I think the exception might have been some Rotary hammers, since AEG and Milwaukee were both owned by Atlas Copco, who I think also owned Kango from the UK.