I have had the same problem starting 11 July.  I was getting the emails delivered appropriately on 10 July.

I have checked spam folder on gmail, no emails from blockchain there.  Interestingly enough if I go to an incognito tab and try to login I will get the "authorize log-in attempt" email.  So it seems like it's not as if GMail is rejecting all mails from blockchain.info.

I opened a support ticket but the initial response suggested checking spam folder and resetting 2FA.