That's usually the case. I have a Simasima SE/30, where looking through the magnifying glass, I have noticed a few traces have ben eaten by the goo in the upper left hand corner where there are 4 caps. Other areas have the solder joints corroded, so my work on that machine is cut out for me - recapping and trace rebuilding.

But similarly, with my Duo collection, many have leaked caps and I'm afraid to look at them but I have too though in time (probably after SE/30 and the Classic II).