The point is, there's nothing to be gained by not finding out one way or another, if his hunch is correct or not. Knowing is better than not knowing, even - maybe especially - when you don't like what you find out.
But that's not how science works. You don't just come up with a random idea and then test it; such a scattershot approach would lead to little forward motion. You look at the evidence and attempt to form a hypothesis that supports all of the available data, and then find a way to test that hypothesis. In this case, his central thesis, "Exploring is dangerous and therefore it must be aliens," is scientifically flawed on multiple levels. First, many dangerous behaviors are not evolutionarily maladaptive or caused by outside forces. Hunting is more dangerous than being an autotroph, but predation is not caused by parasites. Sex creates the risk of STDs, but sexual reproduction is not caused by parasites. A drive to explore leads to potentially vast rewards, particularly in situations of overcrowding, so it's hardly inimical to the existence of a given species to have a desire for novelty. Secondly, it is much more likely that one of the basic drives of human nature is caused by something inherent to human nature rather than by an outside force; we already know a great deal about neuropsychology, and it makes much more sense to seek an answer for human behavior patterns there than in a hypothetical alien parasite. Thirdly, there is no evidence supporting the existence of an alien parasite. No one has ever seen such a thing, and within the world of this story, the Phages are the first aliens we ever encountered; the chances of these same aliens, the only ones we've discovered in a vast, vast universe, being connected to us by a single parasite with a millennia-long life cycle are vanishingly small.
For example, sunspots and flares *might* be caused by giant, invisible alien ships crashing into the star like moths drawn to a flame, but it is much more likely to be caused by some sort of reaction within the star itself. If we're setting up a study and we have limited funds, we're going to give the money to the guys who say "We're examining the effects of electromagnetism on plasma" than to the guy who says "I'm trying to turn invisible so I can determine how the aliens get past us unseen."
So yes. His funding was revoked quite justifiably because he was wasting money and doing bad science. If we eliminate all the obvious causes and are completely at a loss to explain a particular phenomenon, then sure, we can start trying out the more wackball theories. But it just makes more sense to try the obvious first and either establish or disprove them as the source of whatever phenomenon we're studying.
This is far more thought than really needed to go into this, but it is why I was unhappy with the story-qua-story despite my enjoyment of parasites.
