Hellbentthis is really interesting. func_brushes are mainly used in jump maps to make walls where stickies bounce off, but arent used for that anymore since they are really buggy (caused A LOT of wallbugs). Perhaps them being at an angle fixes that and makes them even better than world brushes/func_detail? They would have to be on playerclip though, else stickies will just bounce off the wall.
I know jump_carrot does this and the walls are more difficult to wallbug on than others, but u can still wallbug some. Maybe it's at specific angles? Confusing
i was curious so i did a bunch of tests and basically nothing about it makes sense. i copied a bunch of 45° func_brush walls and placed them everywhere and about 3 out of over 20 prevented wallbugs consistently, while the others were just as buggy as a normal wall. variations in angle and position seem to just have a randomizer effect with a small chance that it'll work and a big chance that it wont. best case scenario is that someone could try putting their func_brush player clip in their map, and move it around in small increments of position/angle until it stops wallbugs, but that seems extremely tedious and far-fetched.
tl;dr dont bother with all of this stuff, making as many of the player clip brushes on snake (and other maps if any other mapmakers are reading this) orthogonal as possible will prevent exploitation in 95% of cases