thank you @IndyMike for all the testing and tables here ! Also @Techman for the heads up about Steve.
As reference my boated (as in too many devices) Insteon / Zwave does pretty well overall. The ALL-ONs which started for me many years ago have greatly reduced as I have dropped out many of my batt devices. I am down to having 1 every 1-2 months typically. I have put numerious work arounds in place to ensure the ALL ONs do not cause significant issues. Some examples include removing/readding the TSTATs when in auto mode with moderate temps set (since the ALL ONs sometimes cause the TSTATs to bounce to whatever they were at when included in ISY), replacing I/O lincs I had on skylights and furnace zones with mimos, replacing key switches with ones, few others over past 8yrs I am not recalling at the moment.
I also created ALL ON and ALL OFF "detectors" with 2 seperate i/o lincs - wiring the relay to sensor input of each unit then leaving relay in state which would be toggled by the signal and lastly setting program that sends a warning text when changed. The phantom signals always impact the relay and not the sensor but you can use the sensor to "reset" the detector.
Silly that I never tested the ALL ON button from ISY devices page - wondering if that does same as the protocol "crash" or whatever we call it that creates the phantom ALL ON ?
I can also report that SwitchLinc Dual-Band Relays starting with 46.xx.xx.xx do not react to all ons