I'm going to go with no.
Here's my reasoning. When people say "blood disorder" that means something wrong with your RBCs, like anemia, something wrong with your WBCs, like leukemia, or something wrong with your platelets (although those often get referred to as clotting disorders, rather than blood disorders. All of these things are fairly easy to diagnose and would be hard to miss on the common blood tests where most of us are normal. When you first went to the doc saying you were tired all the time, anemia was probably one of the first things s/he ruled out.
That's not to say that there's not something off with our blood, like the RBC deformability problems some studies show. But other studies haven't shown, I think? I am certainly not ready to say that ME/CFS is caused by RBC deformability issues, even if that is a component, since I don't think we know that yet. And again because calling it a blood disorder would imply that is both the case and the main treatment target, which I also don't think we know yet.
There is something clearly wrong with blood flow and perfusion, but those types of issues aren't necessarily not something categorized as (or caused by) a blood disorder. You could say I'm arguing semantics a bit, but I think it's more a problem of correct disease classification and identifying the underlying problem as opposed to all the downstream problems.
Prove me wrong, science!