When was that? I've been using blockchain.info now blockchain.com wallet for 4 years now but the first time I sign up it's not asking for a secondary password and I created just last year and its not still not asking for a secondary password, you only need one password here but if you lose that password and you did not store the private key you cannot access it anymore.
Maybe you didn't take time to explore the wallet quite enough and therefore never had it enabled, but have you taken time to read through the responses in the thread?
Because if you did, nc50lc confirms that feature is still there with even a screenshot. Here is the link in case you would like to see the magnified version:
https://imgur.com/LlI0ie6