Perhaps by "hand drawn" they meant "hand taped," the more usual method for circuit layout. While I have done small boards with a photo-resist pen on the copper or a marker on a mylar mask, it was more usual and easier to use a strong black tape on the copper or the mask. It came in varying widths, and you could also buy stick-on or transfer pads for through-holes and sets of pads for ICs. When taping out stuff it was definitely easier to do straight lines than curves!

I think that the giant solder blob underneath the voltage regulator is kind of interesting. I'll have to keep that technique in mind when I need a DIY heatsink in my own projects.

Also kind of interesting are the wrinkly traces. This is due to "hot air solder levelling" (HASL) where the traces were coated with solder before the solder mask was applied, which helped reduce corrosion and with wetting at nearby joints. During the later wave soldering process, the HASL solder would melt again under the mask, and wrinkle as it cooled down. You can see this on a lot of 1970s and 1980s PCBs.