Why are you talking about a situation without admins?
I don't know where
you got this from.
Your proposal to make almost everyone admins is effectively a proposal
to remove admins.
OK, maybe you don't know this yet, but all changes
in MediaWiki can be
undone. There is no such thing as permanent damage.
You can't revert bad press, or hurting someone's feelings, or someone
leaving Wikipedia because of stress, etc. There is definitely such a
thing as permanent damage.