[grkvlt]

> No, I won't sign in with Google, nor Facebook.

That's probably your problem. I signed up for Quora and can read the posts fine. Also, there's a 'close' link under that dialog, which you could have clicked without logging in.

> If the HN homepage had a popup saying "Login with Google or Facebook to read all of HN," would you tolerate it?

Yes. Why not? It seems childish to rail against this. If a site is useful, I create an account. I did that for HN, and it doesn't matter if the sign-in mechanism is proprietary, Google based, Facebook or OAuth. In fact, I trust sites that use external, federalised SSO more because I know they didn't roll their own authentication with associated failures.