This is already available, but it is a bit quirky. If you hold down Ctrl+Alt and click on the collapse divot of a TOP LEVEL group (folder), then it will collapse ALL the groups and ALL the layer effects in the entire document. Doing the same thing to an expand divot for a top level group will have the opposite effect: all layer groups will be expanded, and all layer effects will be expanded.
In practice this works really well. I know it doesn't work as smoothly as what you're suggesting. It would be nice if this would work only on sub-groups, but it doesn't work that way. But in practice, it's good enough and I use it ALL the time.
Edit: Well, now I tested it and it looks like it does work on sub groups. Not sure why I thought it didn't.
After a heap of experiments I found out that it does work on a different arrow. The one that expands/collapses the "folder with layers".
In this case, yes -- it not only collapses all the folders with layers but does also the effects "threads", which solves the issue but with very uncalled for "side effects".