The only logical answer for Linlin/Kaido not having awakening is this;
Mind and
body need to grow / match the fruit of the user to awaken it.
Linlin's mentally deficient and in deep denial about eating her childhood friends + her caretaker.
Kaido is suicidal and deeply troubled by his past battle with Oden.
(King is likely too subservient for a ferocious ancient zoan fruit to awaken)
So the only explanation I can reasonably... Somewhat accept (but am still not happy with) is that Linlin & Kaido's personality flaws prevented them from awakening their fruits. I hate it, I think it's dumb, but if Oda dropped a text bubble and explained it that way, I'd get over it.
Lucci having awakening just to get ragdolled, get back up and run away is ass though. CP0 better not leave Egghead after this wasted time on them, that'll be Greenbull 2.0 in terms of plots that go no where.