Having a CW affiliation shouldn't make you ineligible and it's elitist bull**** to say it should.
That said, having the only notable work on your resume be a few episodes on a CW show and really nothing more goes to show that they are, almost certainly, not qualified to lead a billion dollar franchise and it's foolish to think that they are, based essentially entirely on looks and a few guest appearances.
That's true however as you've mentioned there is a big expectation that you've done some other work aside from your CW show. Also as shallow as Gossip Girl was it still appealed to a wider audience than you're smallvilles and supernaturals really do. It had "buzz" as the cool people like to say.
Which is why Gossip Girl premiered to less than half of what Smallville premiered to?

He's great, but hardly physical or conventionally handsome.
I agree that Benedict exudes great intelligence, but I just think it would be better applied to characters like Brainiac or Dr. Strange.