Here is what I have learned, during my submission journey, and in my related research:
People submitting should understand that agents' form rejection language is a diplomatic way to say no, especially if the response is to an initial query rather than a requested full manuscript. The form rejection is a ritual performance, like a ballet or an interpretive dance. Try to appreciate the elegance and subtlety of the form rejection, but don't read too much into it.
The agent's objective is to make the author go away. The language will usually be polite enough that, if the author's lousy manuscript goes on to become the next lousy bestseller, the author won't be going on "Today" and shouting "In yo' face, Lazy Agent!"
Thus the language will posit the possibility that some other hypothetical agent might agree to represent the work. The author should not read too much into such a statement. The language will be the same whether the query is good, mediocre, or incomprehensible and insane, because the same letter goes out to everyone.
However, the language will generally not be too encouraging, because, if it is, the author will misread it and later claim that the agent liked or recommended the manuscript in subsequent queries to other agents.
Above all, the language will be carefully crafted to discourage the author from replying to the rejection e-mail, calling the agent's office, or showing up in person.
However, despite the hundreds of hours of painstaking craft agents put into their form rejections, authors continue to do all these things. Thus, the ballet continues.
If anyone is doing academic research into linguistics and the limitations of communication, I think author misinterpretation of rejection letters would be a fascinating research topic.