> Cookies can also be queried programmatically,

Misleading statement, essentially untrue.

> Most extensions have effectively full access to your cookies

False.

> There are ofc server set cookies which are not programmatically queryable, but that's not the norm

That is the norm for login cookies.

> and they're still visible via the developer tools,

This is irrelevant to the argument.

I’m quite sure that server set cookies are the norm for authentication, at least where they are set from the server side.