Ah! So that was the service where I was able to continue logging in by selecting Deny/Cancel! I believe in AirTable you can get around this. Not on Dropbox.
OP here. Just to clarify some confusion. I can still login using my username and password. I just liked the simplicity of logging in via Google, since I was already logged in there.
Seems like I'm no longer able to do that and, from what I read here, some users might be completely locked out unless they give access to Google contacts.