Instead of failing to create interfaces with an MTU of 0, would we consider omitting this field instead? It appears to not be a required field by NetBox for Device Interfaces objects:
{"time":"2025-11-17T15:34:04.333799071Z","level":"WARN","msg":"Interface MTU is outside valid range (1-2147483647) or overflows int32","backend":"snmp_discovery","interfaceIndex":".1.3.6.1.2.1.2.2.1.4.988","mappingID":".1.3.6.1.2.1.2.2.1.4","mtu":"0","value":"0"}