This logic makes no sense to me. To me the whole point of a feed reader is to not miss items. So you're saying you went to Twitter so you could "ignore it when you don't want" but that means you never needed a feed reader in the first place.
I mean, if you don't care about missing important items and Twitter works for you that's great. But to me it doesn't solve the problem feed readers are trying to solve.
I don't think that's the original problem at all. the original problem was simply aggregating a bunch of feeds into one page. I use my feed reader a lot and have no problems with using the "mark all as read" button every so often.
I mean, if you don't care about missing important items and Twitter works for you that's great. But to me it doesn't solve the problem feed readers are trying to solve.