Re: ‘Superman & Batman’ movie will follow ‘Man of Steel’
Well the blurb says "weary and tired" not old and worn out, I think it's meant as a contrast to the young and green Superman. In the process of them becoming friends Bruce regains some of his vigor and Clark gains some experience.
The greatest science fiction series of all time is
Doctor Who! And I'll take you all on, one-by-one
or all in a bunch to back it up!"
--- Harlan Ellison, from his introduction
to the PINNACLE series of Doctor Who books