Lead carbonate or flake white was indeed the standard white paint for a very long time. It mixes well with oil ( usually that was linseed oil) and is a good, dense, light-fast white that brushes out very well, which is why artists have liked it. I One quality that made it good for house paint but bad for the environment was that it would ablate: it would wear down and present a clean, chalky white surface for a long time. That also meant that toxic lead carbonate was added to the dirt around the house.

But long before 1978 there was a recognition that lead paint was toxic, especially for children, and long before 1978 manufacturers had discovered the advantages of other vehicles for paints, like acrylics and latex. Titanium oxide white ( commercially available after 1921) and zinc oxide ( available in the later 19th c.) both made very good light-fast white paints, and titanium oxide is very inert. They did not blend into oil vehicles as smoothly as lead white, or make the oil "dry" or oxidize as quickly, but in latex or acrylic house paints that really was not an issue. ( There's still use of red lead paint in the marine industry, though- that seems as though it's hard to entirely replace.)

Personal opinion only: I have used both eutectic lead solder and the new RoHS stuff, and I tend to agree with you that leaded is easier, especially for tiny SMD components. Getting the proper flux is key. Better, probably, is giving up hand soldering altogether and using an oven- like most of the electronics Industry.