Perhaps the injuries that led to the pitch healed between summers. Or has this tree been emitting pitch for many years?

Yes there has always been a fair amount of pitch but last year was amazing. Icicles hanging down. This year. None. I know they damaged the root system about 5 years ago when they put in a retaining wall. Th tree still seems healthy though. It is about 80 feet high and the trunk is likely 3 feet through. Appreciate your interest I find it curious.