I've been using insteon for many years. Fortunately about 5 years ago I migrated to ISY also and ran both hubs in parallel. Since insteon was native to Alexa, I used ISY for major programs and the Insteon Hub for voice commands.
I have about 60 insteon devices in the house and the good news is they all still work in PL and Radio mode. I also have about 20 spare keypads and dimmer switches.
When the Hub went red at first I thought it died but went on line and realized the plug was pulled.
I deleted all the insteon devices from Alexa, installed the Portal and paid the subscription and got the ISY hub up and running in a couple of hours. Still tweaking device names as I have alot of different devices on several platforms.
One get's used to voice control and automation and I am well invested in HA.
Don't know if Insteon will ever come back. I like the devices and may purchase some more just to have some spares. ISY is nice because you can configure alot more parameters... For instance on all my keypads, I was worried about LED's eventually burning out with them lit up 24/7 for in ISY I programed the keypad lights to only come on from sunset to 12 AM and then from 5 AM to sunrise. Lots of versatility in ISY with Insteon