There is a lot more to playing wr than speed. Can they break a jam or press? What is their short, medium or deep route running? What is their football IQ and do they know where the openings in the zone are? Are they a spectacular catch guy?
Remember John Ross? Short deep threat for Dalton and the bengals? Could not break a jam and the bengals didn’t have the line to throw deep if he did. Situation matters.
Dak likes to throw to route runners. Beasley in the slot. Witten at TE. Etc…route runners got separation. Dez was a spec catch guy who never really separated but Romo didn’t mind but Dak never feed him like Romo did. You could say Tolbert is fast, but if he runs sloppy routes, he will be blanketed and Dak will not throw to him. (Not saying anything about Tolbert, just giving an example) Situation matters, scheme matters and know who your qb is and what he likes to do.