No. A work must meet the criterion of "originality" to be copyrightable:
"Creative work must meet a basic level of originality to be considered the product of an author. Direct copies of someone else’s work can’t be copyrighted, and neither can facts, short phrases, titles, etc. For example, the names and addresses in a phonebook can’t be copyrighted but the photo on its front cover most certainly can."
Also, even if you could copyright your password, copyright protects against unauthorized distribution. If Google is merely storing your password, it's not distributing it.
(A single word or phrase, e.g., "Google", can be trademarked, but that specifically involves its use in commerce to identify a brand. But it can't be copyrighted.)
But surely If I created my username & password and they are unique and if I therefore own its copyright, can someone like google copy them to produce a token or other reference that will be used to produce income (for them), doesn't that violate my copyright?
Copyright also protects against use as well as distribution doesn't it?
An example would be if I was to copy a blog post, can I use it for other purposes like using it in it's entirety in a paid teaching class about blogs in general, referencing the words the layout, the subject matter.
But you don't own any copyright, because as "short phrases", they do not fall under the protection of copyright law (see the quotation in my comment above).
I did read the article you quoted. The short phrases referred to in article were common phrases and words.
A password (though possibly short but maybe a sentence) I think should be able to copyrightable. It is unique, it is original (assuming you didn't use a common word, phrase or sentence) and i created it.
Just because I was required to does not seem to me to exclude it from copyright.
The same can be said for an email address, at least the first part up until the domain.
If the actual email name is allocated (by the email provider)then I most certainly do not hold the copyright (the email provider does).
"Creative work must meet a basic level of originality to be considered the product of an author. Direct copies of someone else’s work can’t be copyrighted, and neither can facts, short phrases, titles, etc. For example, the names and addresses in a phonebook can’t be copyrighted but the photo on its front cover most certainly can."
https://www.newmediarights.org/business_models/artist/ii_wha...
Also, even if you could copyright your password, copyright protects against unauthorized distribution. If Google is merely storing your password, it's not distributing it.
(A single word or phrase, e.g., "Google", can be trademarked, but that specifically involves its use in commerce to identify a brand. But it can't be copyrighted.)