Definitely! I've worked on the design of these types of systems, there is more subtlety to the security models than people assume. Some of the designs in the wild have what I would consider to be notable weaknesses.

The most interesting subset of these systems are high-assurance bi-directional data paths between independent peers that are quasi-realtime. Both parties are simultaneously worried about infiltration and exfiltration. While obviously a misnomer, many people still call them diodes...

The entire domain is fascinating and less developed than you would think.