The CW really doesn't have that business model anymore. I don't think you can apply "how things used to work" or even how current networks work on them. They're a bit of an odd one because it's a Warner/CBS partnership (with all shows on the network owned by either or both of them), hence why something like Crazy Ex-Girlfriend is now in its third season. Add that they have to program 15 shows in a season with a 10 hour schedule per week, so some shows inevitably get shorter runs. In fact, before they struck their Netflix deal(s), they were making a loss on the network, so ever since they got it they pretty much changed their business model. You also can't say "a show on another network is doing better and got cancelled so Dynasty should be too" because that's not really how any network operates.