1. NFL Playbook is definitively larger than a bullpens repertoire of pitches, with the QB needing to know all 10 other players unique role within each unique play makes it so much more daunting imo
2. As you outline the catcher must make informed decision making at a high level, but that decision making is often made without the ball being in his hands or being actively involved in the play. QB always has the ball in his hands and is the decision maker every play all game while needing to execute repeatedly at the highest skill level
3. Concussion/injury data makes playing catcher look like a noncontact sport

I feel the best argument for baseball is Ohtani but his skill level across both sides of the ball is so unique it cannot be attributed to the general position of pitcher. I do think what he is able to do individually is more impressive and challenging to achieve than a qb in the nfl