Perhaps tou should more history. It was that bad and worse. Here is an example.
“Convicts who attempted to escape were sent to tiny Norfolk Island, 600 miles east of Australia, where the conditions were even more inhumane. The only hope of escape from the horror of Norfolk Island was a “game” in which groups of three prisoners drew straws. The short straw was killed as painlessly as possible and a judge was then shipped in to put the other two on trial, one playing the role of killer, the other as witness.”
No, it is you who have overlooked significant facts. First of all, you have not answered my statement that convicts/deportees were not chattel, could not be treated as property, i.e., raped, castrated, mutilated at will. Second, you did not answer the fact that the children of convicts/deportees were not property that could be sold, continuing for generations. Third, the deportation was a sort of “final solution” to get rid of the convicts, not a flourishing business, like slavery that was the foundation and cornerstone of an empire.
As to your statement about how harsh conditions were on that penal island, I will point out to you that you are overlooking the salient detail that the prisoners were criminals, being punished - however harshly or unjustly, whereas the Africans were foreigners who were innocent people , captured and enslaved for hundreds of years.