Not the first time to come up
I agree it would be awesome on Switch
That said, I also remember specifically asking one of the Arrowhead people about it at some point and they had said it would be very unlikely.
I think as unlikely as Nintendo would be to put a port of Zelda Breath of the Wild on PS4. That being said, if the Switch is successful, it is possible that Sony will get interested in doing another portable that is more capable than the Vita for something like Helldivers.