Darwin took life as "given" - he didn't ask or answer the question "what is life v non-life/death in nature" nor did he posit a theory of abiogenesis.
In my view, Darwin should have formally declared life as an axiom or postulate in his theory. Contentious disagreements have multiplied from inferences due to that omission.
IMHO, the inferences aren't justified and aren't Darwin's fault. Yes, Darwin took "life" as a given without explicitly declaring that life exists. Falsifying that proposition would indeed cause TToE to fail that seems a totally irrational basis for complaint.
He also did not posit a theory of abiogenesis, or specify an "origin" of life. In the realm of modern science, that complaint seems to be an innovation developed specifically for TToE and "Big Bang" theories. I can't think of any other theories that get faulted for failing to formally declare the existence of or cause of creation of the physical entities they are investigating.
You and I both know that Darwin did not theorize about abiogenesis. His was not a theory of origins of life but rather of speciation, origin of species. Nor was his a theory of what life "is."
But if you were to poll people on the street - or even Free Republic for that matter - you'd probably discover, as I have, that most people are under that impression. And, I suspect for that reason, many of them are upset with Darwin over something he never claimed in his theories in the first place.
When I look at what Darwin actually said it is not all that earth shattering. Living things change and adapt over time. Some are successful, some are not.
Likewise I do not find the intelligent design hypothesis to be all that earth shattering. Indeed, I wouldn't even call it a hypothesis, I'd call it an observation.
It simply says (paraphrased) that "certain features of life and the universe are best explained by intelligent cause rather than an undirected process." And, after all, many creatures are known to choose their mates thus affecting inherited traits. And it is not a substitute for the theory of evolution either, it applies only to certain features. Nor is it a theory of origins. It has no Holy writ, no milk, no meat.
Give me something meaty to chew on! Let's debate what life "is" not what it looks like. Let's look at origins of life, space/time, inertia, information, autonomy, semiosis! Let's discuss the philosophies involved - what can man know, what can he never know! Let's discuss formal cause, material cause, efficient cause and most especially final cause!
And most important of all, let's talk about Jesus Himself!