As far as we know, zoan awakening is the default state and just gives you higher stats.
Well that's the awakening of the zoan users in ID but it is highly unlikely that Oda wastes his first opportunity on a mystic zoan awakening to show a generic ability also shown by fodders?
I rather think that Chopper's Monster Point may be a part of a zoan's true awakening form tbh. This is at least better than a simple endurance and stamina boost if you ask me.
Since Kaido ate a fish DF and probably awakened into a Dragon.
Well ofc that can be part of zoan awakening but it doesn't mean that this stuff is the only thing about his awakening, or not?
If the robot is made out of specific material that keeps gamma radiation away, he won't be harmed.
Sure, and due to the specific material - which makes those robots extremely durable in front of radiation exposure - these robots can withstand some amount of said radiation.
By the way, the chance of avoiding a lethal dose of radiation from a nuclear bomb is the possibility of positioning behind a mountain if the bomb detonates near enough - in which even the radiation exposure would 'kill' you within minutes or even seconds, I don't know - due to the fact that the mountain can absorb a huge amount of radiation as well which increases the chance to not die immediately from such a situation.
Like I said, my knowledge about that isn't really advanced, so if someone needs to debunk what I'm saying, feel free to do it.
And I mean, although it is fiction, we're talking about top tiers who are able to tank earthquake punches point blank on their face, with the energy of a few gigatons.
Moreover, Kaido is known to have the best durability from all the top tiers of One Piece. So if Akainu can withstand such an enormous force with moderate injuries, Kaido should be even less fazed tbh.
So their biological body is hardly comparable to "normal humans". That's why they are freak of natures as well.