I’m not fully convinced the comparison with WiFi/TCP bufferbloat directly applies to ATN B1.
ATN B1 is not a TCP/IP internet-style network with adaptive congestion control. It’s an OSI/CLNP-based ATS datalink architecture with very different traffic patterns, priorities and certification constraints.
That said, the general principle still makes sense: if intermediate ATN/VDL2/ground systems use store-and-forward queues or oversized buffers, congestion could absolutely create variable latency and long delivery times.