From what i've heard the radioactive ones are going to be disabled.
"Radioactive dinos are dangerous, but rewarding. Their radiation pulse boosts the mutation chance of babies by about 5x"
There is something like 15 different shiny powers (not counting the sub categories).
I don't know how many tamable dinos in ark but let say 100-200.
The chances with 10 shinies/24h (cluster wide) to find a radioactive rex/gigas is extremly small and if someone does, so what... That amount of luck should be rewarded
It's way easier to mass breed mutation that to count on the shiny one.
I think it could be a chance for secondary-never-used dinos like velonasaur, rhinos and others to be bred into a powerfull line just because someone found a radioactive one.