Here is a valid logical argument:
People who "design" cruel systems are justifiably considered to be cruel themselves.
Creationists believe that God designed nature.
Nature is a cruel system.
Therefore creationists believe that God is cruel.
That is actually a valid logical argument. If the premises are true, then the conclusion is necessarily valid.
So let's examine the premises.
In regard to the first premise, I can even bring out the Adolf Hitler analogy.
I don't believe that Hitler personally ever killed a single Jew. Yet who gets, quite jusifiably, blamed for the Holocaust?
Because Hitler was personally responsible for the "design" of the Holocaust. (He didn't "design" all of the details, but the basic concept was surely his.)
Therefore, as that example clearly illustrates, "designers" who "design" cruel systems are justifiably considered to be cruel themselves as is the case with Adolf Hitler.
The second premise is: Creationists believe that God designed nature.
Since "nature" is a shorthand way of referring to the living things on Earth, that is surely true. Creationists truly believe that God "designed" nature.
Many creationists contend that God created a perfect nature - one that was not cruel - but that the fall of man caused nature to degenerate to what we see now through a series of "micro-evolutionary" steps.
That is a fallacious argument for two reasons.
First, nature is the cruelest to non-human creatures that live in nature. Things like parasitic wasps don't attack humans. Most of the parasites in nature attack organisms other than humans. Since the creatures that DO suffer are innocent of the fall of man, then **IF** they are being punished, the "designer" is cruel for designing a system that punishes innocent creatures.
Second, a simple case of "micro-evolution" DOES NOT and CANNOT explain much of what we see in nature. My favorite example remains heartworms. They cause pain and suffering in dogs. Dogs surely feel pain.
Yet heart worms are transported from host to host by another parasite - mosquitoes. It is impossible to even hypothesize what the original heatworm "kind" was and how they "micro-evolved" into what we see today.
Therefore that "explanation" by creationists is invalid.
The third premise is: Nature is cruel.
In a poem written about a decade before "The Origin of Species" was published, Tennyson famously talks about "Nature, red in tooth and claw".
More than half of all species of organisms on Earth are parasites. The vast majority of them cause pain and suffering.
We also see other examples of cruel things in nature such as male lions killing all of the young lions in a pride when they take over that pride.
Therefore all three premises are valid.
If you are a creationist and believe that God "designed" nature, then you are obligated to accept the belief that God is cruel.
If you are NOT a creationist then you DON'T believe that God "designed" nature. In that case premise 2 is false and you are not forced to come to the conclusion that God is cruel.
But, to emphasize, creationists, necessarily, believe in a cruel God
If creationists dispute this argument, they must explain which premise is false and explain why. If the say that nature has only gotten cruel since the fall, then they must explain a hypothesis for where heartworms came from in the Garden of Eden.
If they cannot show that one of the premises is wrong, then the conclusion is valid and creationists believe in a cruel God.
Logic doesn't lie.