Account / blog recovery, no matter how righteous, cannot be guaranteed . Some people lose their phone, others get a new job - and some people just cannot remember the email address. Without any possibility to remember the password - or having just caused account lock by trying to guess the password - and without any backup access token , the blog is lost, for good. Right? Yes, and no. The blog can't be updated - but it can be read.
What Blogger won't tell you