I am just guessing here but I assume it is probably something to do with the https://forum.dfinity.org/t/enhancing-network-decentralization-proposals-for-identity-verification-and-subnet-allocation/ as that has been a big talking point lately.
Maybe it is something that the node providers involved do not wish to publicly talk about as they have not mentioned anything either. I am sure all will come out with the wash sooner or later.