I have gotten used to it but I also was never thought is looked cluttered when they didn't disappear.
I agree with this.
On the other hand, I think the italicized/bolded Last Edit message is beyond cluttering, and having that disappear gives the forums a tremendously cleaner look.
Usually I much prefer to have simplicity and functionality at the cost of looks, but the buttons don't seem annoy me as much as everybody else. Even if the quote button doesn't re-appear, I still know where it is (plus the hand icon still shows up) and it functions nonetheless.