You can get MIPS built in to the pads now, so it's less of an issue.
I suspect that the honeycomb will have a different compression pattern to EPS. Generally when tubular structures like that collapse, there is a certain amount of lateral movement anyway.
But MIPS isn't about impact absorption, it's about stopping a roll happening on the skull that leads to concussive damage to the brain.
MIPS is about allowing the helmet to roll independently of the skull to reduce that concussive effect.