to fall (also go) by the wayside

expression, to fail to stay the course, to drop out; to become superseded or neglected (“wayside, n. and adj.” OED); also variation go by the way

“Did they have high school on the Island?”
“Just grade nine and ten, years ago, but it fell by the wayside.”

“In those days they stayed up because of grave robbers and stuff. But that’s gone by the wayside too.”

“The other great thing about this community … no matter what the issue may have been, and there are issues that come and go … If there’s some emergency or some hardship or something that arises, everything else goes by the way, and they’re there for you.”