Each blog had an owner, and members. The owner was the administrator of the blog, and ownership could not be transferred.
This simple policy was a problem, because some blog owners would eventually lose interest in a blog, and want to cede ownership to someone else. In other cases, people were known to die suddenly, leaving blogs with no live owners. In both cases, Blogger Support would become involved, and would manually transfer ownership.
Later, Blogger developed the Permissions wizard, and added a class of member called "Administrator". The original publisher of a blog becomes the first administrator, who may, at his / her discretion, designate additional administrators. That solved the problem of nontransferable ownership, but introduced a second problem. Any administrator could, at her / his discretion again, remove him / herself (or any other administrator) from the administrators list.
Initially, this improvement created two problems.
- Some bloggers managed to remove all administrators from the list, creating blogs with no administrators.
- Some bloggers, newly made administrator, would inappropriately remove other bloggers (including the original administrator aka "owner") from administrative status.
Blogger fixed the first problem, by adding a safeguard - making the Permissions wizard check for the presence of other administrators in the membership list, before removing administrator permission from any one member. However, there remain two problems, now.
- The safeguard works only if you can guarantee that all administrators can perform as administrators.
- This policy works only if you can guarantee that all administrators will perform honourably.
If blog membership is to be fully transferrable, all administrators to a blog have to have equal status. If you have an "owner" class of administrator, and a suddenly dead owner, you have a blog with no active owner. Or, you have blogs with non transferrable ownership status.
So right now, anybody who is a blog administrator is a blog owner. If you make someone an administrator, and that person removes you (and any other administrators) from administrator status, that person becomes the blog owner. And if you have an administrator who dies, you do not prune the administrator list, and you are able to remove yourself from administrator status, you may end up with a blog with no live owner.
The administrator(s) / owner - whoever she / he may be - has the right to decide over disposition of comments and posts - and of who to make a member, and to make an administrator. Blogger cannot, legally, "restore" anybody's previous rights.
If the "owner" deleted the blog, it's going to remain deleted. Contributors, and former "owners", have no say in the matter. If deleted content must be recovered, it may be possible to do this on a page by page (post by post) basis - possibly from blog cache or a blog posts newsfeed.
Possession is the law, for Blogger blogs. If you gave up control (voluntarily or even involuntarily), it's not your blog.