[Cthulhu_]

I'm not sure what the :/ implies, but if you're disappointed by your own folding techniques, spend a bit of time on it, look up some guides, and fold clothes with purpose. or something.

(Rise up against the machines! Folding your own clothes is an act of resistance!)

[mghackerlady]

I've always taken :/ to be a kind of hopeless dejection mixed with apathy. In this case, it seems to convey their disappointment in their skills as well as the futility of improving

[dointheatl]

I read it as an acknowledgement that while improvement is possible, the requisite effort will in reality never be expended

[IIsi50MHz]

I use it for "disconcerted", but I guess any situation that would result in a diagonal mouth irl would be fine.