With new bookmark managers for some reason they're usually a website, and no matter how good the design choices are, I just won't use it. Not because it's not amazing, but because not integrating it into the browser makes my life more difficult. Not a critique of your product, just an opinion.
I think the difference with other product is that this product is focusing on reading the content, so for example if I want to read a news and there are a lot of ads we can get rid of it, and we no longer need to visit that website directly you can read it in readclip.