When you ask the question "Is this universe capable of sustaining intelligent beings capable of asking questions?" you should not be surprised when the answer is yes. The very fact that you are asking the question is sufficient to answer it. Never the less many cosmologists and theologans seem genuinely amazed by what they take to be the fine tuning of the physical constants (and indeed the scientific laws) that allow our existence.
There are several variables in the standard model of physics that, if varied, could render life as we know it impossible, through various mechanisms (we can call these universes "perturbed universes"). Many argue further that the universes that would result from such variable tweaking seem so ghastly that no other intelligent life could live there.
There are several major problems with the reasoning in these arguments:
1) Calculating the probability of intelligent life existing in a perturbed universe is very dodgy. You are presuming yourself capable of simulating to the necessary degree of accuracy the formation of an entire universe. Physicists are clever but not that clever.
2) The probability of intelligent life existing in these perturbed universes is not the probability of intelligent life existing in any randomly chosen universe. To calculate this you need not only consider universes like ours but all sorts of universes with completely different laws of physics. We tend to assume that other universes would necessarily be like ours. Maybe bigger, smaller, with weaker gravity or with an extra force. Universes similar to our own are an inconceivably small fraction of all possible universes.
3) It presumes that our universe is the only universe to exist. This would seem to be an incredibly arbitrary way for things to be. Why should this one universe out of the infinitely many possible universes be the one that exists? Indeed the only non-arbitrary way for things to be would be for all possible universes to exist (this is what I believe).
One argument against this invokes Occham's razor "Assuming all universes exist multiplies entities beyond necessity.". This is not really problematic because you can regard Occham's razor as being a tool used only to deduce which universe you are in. Under this view Occham's razor is not meant to answer philosophical questions or mathematical questions but just empirical questions.
4) Some universes (we will call them bubble universes) will have the interesting property of containing causaly disconnected regions. These may seem like entire universes from within themselves. It is also possible that such a bubble universe should contain simalcrums of all possible simply definable universes within it (call it a super bubble universe). A super bubble universe will certainly contain intelligent life somewhere within it as it will contain a simalcrum of a universe with life in it. What is the probability of super bubble universes? We don't yet know. I'm guessing 100% though.
5) We shouldn't throw out the possibility of non-living intelligences.
Anyway as you can see I have real trouble with a statement that the probability of intelligent life existing is very low. I would tend to say that all possible universes exist. I will discuss that in another post.