That sounds like a load of old horse droppings. I don't believe that the hub LED colours have been changed, and in the highly improbable situation that they have, VM haven't told themselves, because the public guidance is still that a red LED means overheating.
In modem mode the light has always looked red-ish when viewed off axis, but should be a pinky-purple ("magenta") when viewed face on. If it is definitely red then the hub is signalling that the CPU is overheating. Usually there's no external symptoms like the hub feeling hot, because the total heat output is the same, it is just that for some reason the heat isn't being conducted away from the CPU. So what would be expected is that the CPU either/both throttles down and reduces performance, or the high temperature causes errors leading to disconnections.
There's a simple test, and that's to reset the hub (using the pinhole on the back of the hub), let it come back on line, that will be in router mode until you put it back in modem mode. Let it stay in router mode for a good few hours. If after prolonged running the hub shows a red light, it is overheating and needs replacing, or the thermal detection has gone wrong, and that still needs replacing.
If the hub LED stays white in router mode, then you should be OK to flip it back into modem mode and put the colour down to sample variation, so long as the connection is solid and reliable with no dropouts.
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