Aside from what Bob said, a rope pull CAN be used with a "Safety Relay" for sure, and one can make a logical argument for it based on the redundancy and reset procedure if nothing else. But in the US, this is not (yet) mandated. Most people I know using rope/cable pull switches for safety on conveyors still do so with a Master Control Relay (MCR) as it has been done for decades. Same basic concept as a safety relay really, just not as involved in certifications and no built-in cross checking or redundancy.
But back to the Snart MCC aspect; SOME devices inside of smart MCCs can be fitted with "Network Safety" cards that can be used in conjunction with "Safety PLCs" and things like rope pull switches so that the E-Stop or MCR circuit wiring to each device in the MCC can be eliminated. But it's not a mix and match situation, the entire safety system but be designed and validated as a complete entity. Some people do it because there are multiple safety systems involved and they can all be coordinated better that way, but for most people this is an expense they tend to avoid. If the EU type safety regulations ever make it into our law books, this may change, but so far no.